Microsoft cofounder Paul Allen published a long, detailed review of Windows 8 today on his blog. He praised the new OS but also had a pretty long list of complaints about it.

Allen, who left the company years ago to pursue a career as a tech investor, has been using a preview release of Windows 8 for a few months on two devices, a traditional PC and also a tablet, the Samsung 700T.

That's the same tablet Microsoft gave away to developers about a year ago, when it launched the developer version of Windows 8 at its annual Build conference.

Overall, he says he liked the new OS:

I'm impressed with its clever integration of a bimodal interface to simultaneously support both desktop and tablet use in the same operating system. I found the gesture navigation on the tablet to be quite satisfying and responsive. And in general, I find Windows 8 to be snappier and more responsive than Windows 7.

But he pointed out that Windows 8 was far from perfect:

I did encounter some puzzling aspects of Windows 8.

These are his complaints:

• Some apps, like Internet Explorer, come in Tablet and Desktop modes. But they are really different applications with the same name and function, so it's confusing when both versions are open at the same time.

• Those different applications don't always share information. "Bookmarks I create in Windows 8 style IE are not available in IE when run from Desktop," he says by way of example.

• There is no way to set Desktop as the default view when using Windows 8 on a traditional PC and not a tablet.

• There are no "visual clues" that more commands are available for some applications. You have to swipe or right-click to hunt them out.

• It takes two steps to get to commands that used to be on the Start button like Sleep, Shut Down, Restart. These are part of the Charms menu now, with no "Power Tile" available for it—meaning you can't make a shortcut to it and put it on the Start screen.

• Closing an app is easy on a tablet. Just swipe down. But it's odd for a PC, requiring using the mouse to imitate the swiping motion. This is "not anywhere near as intuitive."

• The traditional F1 key only launched help from the traditional desktop view, not the Windows 8 view.

• There's no way to keep the Start screen permanently visible, to be used as a "dashboard of sorts" with dual monitors.

• So many functions rely on the new Charms menu (Start, Sleep, Print), but when using dual monitors, finding the magic corner of the screen to display the Charms menu is difficult. Allen calls the Charms menu "elusive."

• Windows will suddenly switch itself between Windows 8 mode and Desktop mode. Allen discovered that's because when you create a file, it is associated not just with its app (Word or PowerPoint) but also the Windows 8 or Desktop modes.

• Windows doesn't support folders on the Start menu. You can only add tiles to it, which makes it bigger and bigger. Allen points out that iOS and Android already support folders.

He also didn't like how hard it was to scroll on a tablet when using a Desktop view app, the fact that the onscreen keyboard doesn't ever appear automatically, and the lack of a clock on the Start screen, among other nitpicks.

Allen thinks that Microsoft will fix a lot of these things in the next release of Windows 8. Or he thinks that industrious third-party app developers will come up with apps or fixes for them. For instance, a live tile clock app has already been developed, he notes.

Please follow SAI on Twitter and Facebook.

Join the conversation about this story »

If you'd founded a tech company worth billions of dollars, what would you do with your cash?

That's a high-class problem faced by the moguls on this list.

Naturally, many of them buy expensive things, like cars, houses, planes—even islands.

But even if you're Larry Ellison, with a seemingly endless appetite for that stuff, there comes a time when you want to do more.

Maybe it's solving the world's problems, or just indulging in a geeky fantasy.

Larry Ellison: Anti-aging

Oracle cofounder and CEO Larry Ellison is known for pet projects like running the America's Cup sailboat race series, buying homes on Malibu's "Billionaire's Beach," and turning the Hawaiian island of Lanai into a sustainable living lab.

But he says his biggest philanthropic endeavor is medicine.

"I have a medical foundation called, very creatively, the Ellison Medical Foundation," Ellison said in an interview at the D: All Things Digital conference last year. "We are focused on diseases related to aging—I mean, for obvious reasons." (Ellison is now 68.)

Ellison spent about $1 billion on this foundation.

Bill Gates: High-tech toilets

Through the Bill and Melinda Gates Foundation, the Microsoft cofounder is working on a lot of social issues in health, education, and agriculture.

But one problem that really caught Gates' attention is ... poop. The foundation sponsored a "Reinvent the Toilet" fair. Gates himself judged the entries and announced the winners. 

He was looking for methods "for capturing and processing human waste and transforming it into useful resources," Gates said in a blog post announcing the winners.

Paul Allen: Brain research, sports teams, and collectibles

Paul Allen, Microsoft's other billionaire cofounder, also has a long list of pet projects that includes owning multiple pro sports teams, building a rock-and-roll museum, collecting vintage WWII planes, and more.

He's also invested a half billion dollars into the Allen Institute for Brain Science. Its mission is to figure out exactly how the brain works and how to solve diseases like Alzheimer's, which his mother suffered from.

Another goal of the institute is to replicate the brain and build machines with human intelligence.

Please follow SAI on Twitter and Facebook.

With great wealth comes great responsibility.

That's how we judge the tycoons of tech. While many of them spend their money on expensive luxuries, like cars, houses, planes — even islands — they are also expected to use their prosperity to do good works.

That's the implicit demand of the tech industry.

Some are astoundingly generous, giving tens of millions —even hundreds of millions — to their favorite causes. How much they give says a lot about them. Which causes they support does, too.

SEE ALSO: MISSING OUT ON BILLIONS: These 10 People Made Some Of The Saddest Choices In Tech History

Larry Ellison: A cure for aging

Larry Ellison is known for his extravagant lifestyle filled with cars, airplanes, mansions, even a Hawaiian Island. But he's a big philanthropist, too, giving to his own Ellison Medical Foundation.

Ellison jokes about it: "We are focused on diseases related to aging—I mean, for obvious reasons." (He's 69.)

But it's no joke. He's trying to cure diseases like Alzheimer's and arthritis. And he's generous. The foundation awarded 70 new grants, giving away $46.5-million last year alone, reports Philanthropy.com

Bill Gates: Improving life everywhere, especially below the waist

Through a $3.3 billion donation to the Bill and Melinda Gates Foundation, the Microsoft cofounder is trying to fix lots of the world's problems. He's eradicating polio, trying to end poverty, improving education.

But some of his causes are more fundamental. For instance he's working on better ways to dispose of poop. The foundation sponsored a "Reinvent the Toilet" fair with the winners picked by him.

He's also offering $100,000 to anyone who can make a condom people actually like to use.

Paul Allen: Replicating the human brain

Paul Allen, Microsoft's other billionaire cofounder, is also known for an extravagant lifestyle that includes owning multiple pro sports teams, massive collections, building music museums.

He's invested a half billion dollars into the Allen Institute for Brain Science. It will study how the brain works with a goal of curing diseases like Alzheimer's, an illness his mother suffered from. And ultimately, institute has another goal: to replicate the brain and build machines with human intelligence.

Please follow SAI on Twitter and Facebook.

What would you do if you were a billionaire and wanted to go to space?

The obvious answer: use that money to start a company to help you do just that.

Skip directly to our roundup of space startups >

In recent years, some of the most famous names in tech, like Microsoft's Bill Gates and Paul Allen, Google's Larry Page and Eric Schmidt, and Amazon's Jeff Bezos have been founding and investing in companies that are looking to the stars.

Whether for personal dreams of adventure or for profit, these companies are doing the engineering and basic science needed to get humans into space. 

They're also looking at other opportunities that space provides, like access to resources that are hard  to get on Earth and the ability to collect information about our planet from a different perspective.

SpaceX: The "other" company from Tesla founder Elon Musk. In the short term, it's building rockets and capsules to get astronauts to the International Space Station. In the long term, it's looking to make trips to Mars somewhat affordable by creating rockets that can be used many times, like the "Grasshopper" below, which can take off and land instead of simply falling into the ocean.

Planetary Resources: With financial backing from Google's Larry Page and Eric Schmidt, "Avatar" director James Cameron, and others, Planetary Resources is looking at revolutionizing the tech world by mining nearby asteroids for metals that are extremely rare on Earth but found in abundance in space.

Blue Origin: Amazon CEO Jeff Bezos is well-known for his love of all things space. While he founded Blue Origins in 2000, it's only in recent years that he's become more open with the progress his company is making towards making manned spaceflight affordable.

Google isn't the only big name in tech working on a "cure" for death, or at least a cure for a lot of the things associated with aging.

Venture capitalist Peter Thiel, Oracle CEO Larry Ellison and Microsoft cofounder and angel investor Paul Allen are all working doing the same.

Peter Thiel, who earned his billions largely thanks to backing Facebook in its early days, finances medical research that could help people live to be 150 years or more. He once said that he doesn't believe that people really, truly have to die.

His Thiel Foundation has supports a bunch of anti-aging projects like Aubrey de Grey's Strategies for Engineered Negligible Senescence, which hopes to reverse aging, and the Machine Intelligence Research Institute (MIR), which is working on artificial intelligence. His foundation's newest project, called Breakout Labs, funds startups working on radical science technology.

Larry Ellison may be better known for his extravagant lifestyle than his philanthropy, but he is a generous donor, too, particular for medical projects. He has created his own Ellison Medical Foundation.

Ellison jokes about it: "We are focused on diseases related to aging—I mean, for obvious reasons." (He's 69.)

It's no joke. He's trying to cure diseases like Alzheimer's and arthritis. The foundation awarded 70 new grants, giving away $46.5-million last year alone, reports Philanthropy.com.

Paul Allen, Microsoft's other billionaire cofounder who is also known for an extravagant lifestyle, is interested in curing diseases associated with aging, too.

He's invested a half billion dollars into the Allen Institute for Brain Science.

It will study how the brain works with a goal of curing diseases like Alzheimer's, an illness his mother suffered from. And ultimately, institute has another goal: to replicate the brain and build machines with human intelligence.

SEE ALSO: These 15 Tech Billionaires Are Spending Millions To Save The World

Join the conversation about this story »

Forbes put out its annual list of the richest people in America and it includes 28 people that own sports teams.

These 20 people own a total of 24 teams in the four major North American sports leagues, including 10 NBA teams, 9 NFL franchise, 4 NHL teams, and just one MLB club. In addition, several own other teams in the WNBA and the English Premier League.

All of them, however, have made their money outside of the sports world.

#19t Herb Simon

Estimated Net Worth: $1.95 billion

Forbes Rank: 293

Age: 78

How he got his fortune: Real estate

Teams owned: Indiana Pacers (NBA), Indiana Fever (WNBA)

Championships: One (2012 WNBA Championship)

#19t Robert Pera

Estimated Net Worth: $1.95 billion

Forbes Rank: 293

Age: 35

How he got his fortune: Chief Executive Officer, Ubiquiti Networks Inc

Teams owned: Memphis Grizzlies (NBA)

Championships: None

#18 Robert McNair

Estimated Net Worth: $2.0 billion

Forbes Rank: 273

Age: 76

How he got his fortune: Energy

Teams owned: Houston Texans (NFL)

Championships: None

Paul Allen, the billionaire cofounder of Microsoft and owner of the Seattle Seahawks and Portland Trail Blazers, needed new digs a bit south of his home town of Seattle.

So he just bought a massive 22,000-square-foot custom home in the affluent Silicon Valley town of Atherton, Calif., reports Realtor.com's Neal Leitereg on the Celebrity Real Estate blog. He paid $27 million which was a bit of a deal. The home was listed in late September for $31.8 million, according to Leitereg.

Allen owns properties all over the world. But he may have wanted these digs because his venture investment firm, Vulcan Capital, opened an office in nearby Palo Alto in April, reports the Silicon Valley Business Journal's Nathan Donato-Weinstein.

Atherton is a popular town for tech billionaires of a certain era. Google’s Eric Schmidt, HP's Meg Whitman, and Oracle’s Mark Hurd have homes there.

The home was built in 2013 by Pacific Peninsula Group and sits on nearly two acres.

It has a light, modern design.

Beautiful built-ins run through the home.

Microsoft cofounder and billionaire tech investor Paul Allen has finally sold his 292-acre private island off the coast of Washington, according to the listing on Redfin (via Curbed Seattle).

Allen had reportedly tried to sell the island for years, first listing it in 2005 for $25 million and dropping the price to $13.5 million in 2011.

The final listing price for the land was $8 million, though a final sale price and buyer have not yet surfaced.

The property, Allan Island, is named after a Navy hero and not its former owner, according to the Examiner. The island is accessible by private plane or boat, and while it has a log caretaker's cabin, it has no main house—though there are plenty of scenic spots on which to build one.

A bird's eye view of 292-acre Allan Island.

It sits off the coast of the city of Anacortes, Wash., near Skyline Marina between Burrows Bay and Rosario Strait.

There's a log caretaker's cabin, but no main house.

"Tatoosh," a 303-foot yacht belonging to Microsoft co-founder Paul Allen, is no longer for sale after it failed to find a buyer in almost four years on the market, the Daily Mail reports (via JustLuxe).

Allen first listed "Tatoosh" with Fraser Yachts for $160 million back in 2010.

In addition to accommodations for 20 guests and 30 crew members, the superyacht also boasts a cinema, swimming pool, basketball court, recording studio, gym, and two helipads. 

Allen has made an effort to draw interest to the yacht since it was first put up for sale in 2010. Shortly after it was listed, he let Paris and Nicky Hilton use it for a month-long vacation. Paris raved about it:"I'm in heaven on the water. Definitely the biggest and best yacht everywhere we go. Love it! Huge!"

The yacht was also by far the largest to travel to Sochi for the Winter Olympics last month. 

Still, the publicity hasn't helped to get "Tatoosh" off Allen's hands. 

"‘The yacht has not been sold, and furthermore is not for sale," Stuart Larsen of Fraser Yachts said to the Daily Mail. 

Allen also owns another, much bigger yacht: the 414-foot "Octopus," which has played host to some wild New Years' parties and visits from recording artists like Mick Jagger and Damian Marley. 

SEE ALSO: Google Ventures Founder Sells Palo Alto Home Next To Tim Cook's For $3 Million [PHOTOS]

WE'RE ON PINTEREST: Follow Us Here

Join the conversation about this story »

Some billionaires choose to spend their money on huge mansions and swanky cars. Others use their disposable income in a less flashy way. 

As tech entrepreneurs have seen their companies grow and become financially successful, many have turned to art collection as a pastime and form of self expression.

"An engineer will look at a photograph or video art in a way a banker couldn't — we think in ones and zeros, we think in terms of screens," tech entrepreneur and collector Trevor Traina said to the Wall Street Journal last year. 

We've come up with a list of the biggest art aficionados in the tech world. These executives all have their own unique sensibilities — Oracle CEO Larry Ellison, for example, owns a huge collection of Japanese art, while Yahoo chief Marissa Mayer prefers quirky pop art like Jeff Koons' balloon dogs. 

With a collection that reportedly contains as many as 500 pieces, Oracle founder Larry Ellison is a big fan of Japanese art.

According to SF Gate, the Oracle billionaire first became interested in the art of Japan when he worked there in the 1970s, and he "personally studies and approves every proposed acquisition." Pieces from his collection were on display at San Francisco's Asian Art Museum last June. 

Ellison's preference for the Eastern style is also apparent in his home in Woodside, Calif., which was modeled after a 16th-century Japanese emperor's residence. He reportedly rotates the artwork in his home every other week, in keeping with traditional Japanese practices.

Famed VC Marc Andreessen favors contemporary art.

Midcentury artists Robert Rauschenberg and Jasper Johns are among the famed Silicon Valley investor's favorites, according to Businessweek. 

Andreessen's wife, Laura Arrilaga-Andreessen, holds two degrees in art history and reportedly carries a lot of weight in the process of deciding what pieces they buy for their home. 

The offices at Andreessen Horowitz are also filled with abstract art pieces, including Roy Lichtenstein's "Reclining Nude, 1980."

Yahoo CEO Marissa Mayer prefers "happy art."

Mayer is known for having a sophisticated sense of style, regularly wearing glamorous pieces by Oscar de la Renta and Carolina Herrara.

She also has a taste for quirky pop art — according to Vogue's August 2013 profile on Mayer, the Yahoo executive has several balloon dog sculptures by Jeff Koons in her kitchen, in addition to works by Roy Lichtenstein. She also reportedly owns several glass sculptures by Dale Chihuly, which sell for an average of $15,000 each. 

Mayer serves on the San Francisco Museum of Modern Art's board of trustees. 

Inside Philanthropy has come up with a new list of the most generous donors in tech, basing the ranking on the size of their donations relative to their overall wealth. 

The names who made the list may seem surprising, especially compared to other rankings of philanthropy. While the Chronicle of Philanthropy creates a list of the 50 largest donors any given year, this list in particular uses relative generosity as its main criteria. 

12. Michael Dell

The Michael and Susan Dell Foundation has given away nearly $1 billion since 2000. Those donations, in addition to gifts made outside of their foundation, are equal to about 10% of their estimated net worth of $17.5 billion. 

11. Paul Allen

The Microsoft co-founder gave away $327.6 million in 2011, making him the most generous American of that year. He's given away just over $1.5 billion of the estimated $16 billion he's worth. 

10. Mark Zuckerberg

The 29-year-old's $992-million gift was the single biggest donation of 2013. He's donated about $2 billion of his wealth, which is now estimated to be $28.5 billion. 

9. Pierre Omidyar

E-bay founder Pierre Omidyar and his wife Pam have given away more than $1 billion, donating $225 million in 2013 alone.  

8. David Bohnett

Bohnett made $300 million when he sold GeoCities to Yahoo! in 1998. Since then, his foundation has given away nearly $53.5 million to charitable causes, with a special focus on the LGBT community. 

7. Irwin Jacobs

The Qualcomm founder and his wife Joan have been very generous over the past few decades, donating around $500 million of their fortune, estimated at $1.8 billion. 

6. Jeff Skoll

When eBay's first president signed the Giving Pledge, he said he hoped to donate nearly all of his $3.8 billion "to the betterment of humanity." 

5. Tim Gill

Gill made about $500 million when he sold Quark at the height of the dotcom boom. His foundation has given about $240 million towards LGBT initiatives. 

4. Ed Scott

Scott, who made his fortune with a software company called BEA, isn't at the Forbes 400 level, but Inside Philanthropy describes him as "Silicon Valley's most effective global giver." His donations have gone towards fighting global poverty and disease, as well as projects to find better treatments for autism. 

3. Bill Gates

Gates has donated more money than any other living person, but he wasn't first on Inside Philanthropy's list because his current net worth is $76 billion, nearly twice the endowment of the Bill and Melinda Gates Foundation. 

2. Gordon Moore

Intel co-founder Gordon Moore and his wife Betty put about half of their wealth into their foundation in 2011. It has since made about $3 billion in grants, focused mostly on scientific research and Bay Area charities.

1. Leonard Bosack and Sandy Lerner

 The Cisco co-founders have given more than anyone else, relative to their total wealth. They made $170 million when they walked away from their company in 1990, but they gave about 70% of that money away to charity. 

The Least Generous Tech Leaders 

Inside Philanthropy also compiled a list of the least generous people in tech. Though these executives have made valuable contributions to charity in the past, IP argues that these six people have donated the least amount of money compared to their total amassed wealth.

Among the biggest offenders are (not ranked): Jeff Bezos, Larry Page, Steve Ballmer, Larry Ellison, Jerry Yang, and Michael Birch. 

SEE ALSO: Here's What Bill Gates Thinks When People Say He Should Feel Bad About His Wealth

Join the conversation about this story »

The New York Post's Page Six is reporting that Microsoft co-founder Paul Allen has sold his Malibu home for $28 million. 

The buyer is reportedly CBS President and CEO Les Moonves. 

Allen paid $25 million for the gorgeous white-walled contemporary home in 2010, though he apparently spent little time there since the sound of the ocean kept him up at night, a source told the Post. He "hated the sound of the ocean," the source said.

The house is located on Malibu's ultra-pricey Carbon Beach, a stretch of oceanfront property that's been dubbed "Billionaire's Beach" for its many high-profile residents. David Geffen, Jeffrey Katzenberg, Eli Broad, and Larry Ellison all own property here, with Ellison owning as many as a dozen. 

SEE ALSO: A Silicon Valley Banker Is Selling His Enormous Mansion With A Speakeasy And Ballroom For $27 Million

WE'RE ON INSTAGRAM: Click Here To Follow Us

Join the conversation about this story »

Oren Etzioni is one of the big names in the Seattle-area tech scene thanks to his fantastic string of startup successes stretching from 1994 to 2013. Six startups, all successful exits, including one sold to Microsoft for about $110 million in 2008, and Decide.com acqui-hired by eBay last year.

He's also known for his decades-long role as a computer science professor at the University of Washington, where he's published truckloads of papers since 2004.

In other words, the man didn't exactly need a job. But Microsoft co-founder Paul Allen lured him away for a project too intriguing to turn down: running Allen's Institute for Artificial Intelligence, otherwise known as AI2. Together Allen and Etzioni want to create a computer so smart, with reading, reasoning and learning skills so great that it can pass classes and tests designed for humans.

This is not to be confused with the original, and somewhat related, Allen Institute for Brain Science, with a mission of understanding of the human brain and to further neuroscience research.

Allen is known for his extravagent lifestyle, museums, the $1.5 billion he's donated to charitable causes, and his investment firm Vulcan. He also owns two professional sports teams, the Seattle Seahawks football team and the Portland Trail Blazers basketball team.

Etzioni has been six months on the job. Not only is he thrilled with his new career, he tells us, but he also received one of the best employee perks we've ever heard of:

Business Insider: About your job at Allen's AI institute. You left your job as a professor at UW to do this, right?

Oren Etzioni: Yes.

BI: What is one great project the AI institute is working on?

OE: We are building a program, called Aristo, that seeks to understand science at the level of a fourth-grader and prove it by taking a standardized science test (that it hasn’t seen before) and acing it.

That problem forces us to study fundamental problems in AI in understanding language, reasoning, and much more.

BI: What's it like to work with Paul Allen? Does the job come with access to Seahawks and Trail Blazers games?

OE: Paul Allen is very involved with (and passionate about) our intellectual challenges. I literally had a brain-storming sessions with him today.

My wife and I had the huge privilege of being invited to attend the Super Bowl. We got to watch the Seahawks win, and even attend the after party with the players, which was incredibly generous of Paul and the best perk I could imagine.

SEE ALSO: Salesforce.com showers employees with breathtaking views, swag and doggy daycare

Join the conversation about this story »

Forty European and American landscapes from the art collection of Microsoft co-founder Paul Allen will soon go on display at two art museums in the Pacific Northwest.

The exhibit, called "Seeing Nature: Landscape Masterworks from the Paul G. Allen Family Collection," covers five centuries of masterpieces from Allen's collection. It will be shown at the Portland Art Museum starting in October 2015, and at the Seattle Art Museum in Allen's hometown starting in September 2017, the museums announced today.

“Paul Allen is one of the Northwest’s most significant art collectors and philanthropists,” said Brian Ferriso, director of the Portland Art Museum. “His willingness to share his landscape masterpieces with our visitors continues his exceptional generosity and is a wonderful opportunity to be inspired by works of art that reflect his personal vision.”

The collection includes depictions of Venice by Canaletto, Édouard Manet, Claude Monet, and J.M.W. Turner, as well as five landscapes by Monet. Works by 20th century artists, including Georgia O’Keeffe, Edward Hopper, David Hockney, Gerhard Richter, and Ed Ruscha will also be featured.

Allen is a well-known collector and philanthropist whose family foundation has given more than $100 million to arts and culture causes since 1990. He has loaned out hundreds of pieces from his private collection to dozens of venues over the years.

Take a look at some of the works that will be featured in "Seeing Nature," below.

SEE ALSO: The 12 Biggest Art Collectors In Tech

Join the conversation about this story »

A painting reportedly owned by Microsoft co-founder Paul Allen sold for an astounding $56.2 million during an auction at Phillips in New York City earlier this week, Bloomberg reports. 

The piece was "Untitled (Red, Blue, Orange)," completed by modern artist Mark Rothko in 1955. Rothko works are extremely valuable — a similar painting sold for $66.2 million at Christie's earlier this month.

Allen bought the work for $34.2 million in 2007, and he was guaranteed an undisclosed minimum amount regardless of how much it sold for this week. 

The $56.2 million Allen's painting fetched made up for 43% of total sales for the night's auction, which also featured pieces by Andy Warhol and Jean-Michel Basquiat. The night's $132 million total was the auction house's highest tally since November 2010. 

According to Bloomberg, many stylish young people were in attendance, including Leonardo DiCaprio and Christie's contemporary art specialist Loic Gouzer. 

SEE ALSO: Take A Look At Microsoft Co-Founder Paul Allen's Incredible Collection Of Landscape Art

WE'RE ON PINTEREST: Click Here To Follow Us

Join the conversation about this story »

Everybody knows Microsoft co-founder Bill Gates,  the richest man in the world. 

But Microsoft's other cofounder, Paul Allen, has only become famous (outside of Seattle) since he published his memoirs in 2011.

He, too, is plenty wealthy, the No. 55 richest man in the world, worth $16 billion.

With his money, he's invested in a lot of tech companies, real estate, and art. But he's also led an over-the-top life filled with rock and roll parties, collections, yachts, and sports teams.

Can you spot Paul Allen from this famous photo of Microsoft's earliest employees?

He's the guy in the bottom right.

This is what Paul Allen looks like today.

Allen describes himself on his website PaulAllen.com as a "Philanthropist, investor, entrepreneur, Seahawks and Blazers team owner, guitarist, neuroscience supporter, space pioneer & Microsoft co-founder."

He's all those things and more.

He doesn't just party with rock stars, he jams with them.

Allen plays guitar, and has his own band, "The Underthinkers," who cut an album in 2013. Allen wrote or cowrote every song on it.

According to gossip in the Seattle music scene, he keeps several musicians on full-time retainer. They must be ready to hop on a plane and fly anywhere in the world to jam with Allen and rock star party guests like Eric Clapton.

The album featured guest performers Ann and Nancy Wilson of Heart, Chrissie Hynde, Joe Walsh, Derek Trucks, Doyle Bramhall, David Hidalgo of Los Lobos, Ivan Neville, and others.

Year after year, Paul Allen's party aboard his massive "Octopus" yacht is one of the hottest after-hour tickets of the Cannes International Film Festival.  Models, socialites, and major players in the film industry turn out in droves to dance and enjoy the fine accommodations aboard Allen's  yacht. 

This year's party took place Monday night with Sharon Stone, Adrian Grenier, Russian actress Svetlana Metkina, and model Natasha Poly among the big names in attendance. 

The party is notoriously secretive and exclusive, but here's what you missed if you didn't score a spot on the guest list.

The party took place on Allen's 414-foot "Octopus" yacht, one of the biggest yachts in the seas. 

The decks were set up for dancing.

Lots of beautiful people were in attendance, including designer Gabriela Cadena, model Selita Ebanks, and fashion PR maven Karla Barbosa.

Action star Dolph Lungren and girlfriend Jenny Sandersson made an appearance.

Allen entertained his guests with an impromptu live performance. He rocked out on guitar while "Entourage" star Adrien Grenier played a mean harmonica.

Guests got to take a look around the yacht, including the submarine Allen keeps onboard.

They also checked out the yacht's underwater viewing room, where you can relax and watch the ocean go by. 

SEE ALSO: The Fabulous Life Of Microsoft's Other Billionaire Cofounder Paul Allen

WE'RE ON INSTAGRAM: Click Here To Follow Us

Join the conversation about this story »

Microsoft cofounder Paul Allen threw an exclusive party on his enormous "Octopus" yacht yesterday. The annual event is one of the hottest tickets at the annual film festival in Cannes, France, drawing a long list of celebrities and socialites.

One highlight of the party was Allen's performance with "Entourage" star Adrian Grenier. Allen plays in a band called "The Underthinkers," who released an album called "Everywhere at Once" last year. It features guest performances from members of classic rock bands Heart and the Eagles, and Allen wrote or co-wrote each song. 

Watch him rock out on the guitar, with Grenier on the harmonica. 

SEE ALSO: Microsoft Billionaire Paul Allen Threw An Ultra-Exclusive Party On His Yacht In Cannes [PHOTOS]

WE'RE ON INSTAGRAM: Click Here To Follow Us

Join the conversation about this story »

Forbes put out its annual list of the richest people in America and it includes 28 people who own sports teams.

Friday, former Microsoft CEO Steve Ballmer put in a huge $2 billion for the Los Angeles Clippers, the Los Angeles Times is reporting. Former owner Donald Sterling still has to accept the deal, but if Ballmer buys, he'll join this exclusive list.

These 20 people own a total of 24 teams in the four major North American sports leagues, including 10 NBA teams, nine NFL franchise, four NHL teams, and just one MLB club. In addition, several own other teams in the WNBA and the English Premier League.

All of them, however, have made their money outside of the sports world.

19. (tie) Herb Simon

Estimated Net Worth: $1.95 billion

Forbes 400 Rank: 239

Age: 79

How he got his fortune: Real estate

Teams owned: Indiana Pacers (NBA), Indiana Fever (WNBA)

Championships: One (2012 WNBA Championship)

19. (tie) Robert Pera

Estimated Net Worth: $1.95 billion

Forbes 400 Rank: 239

Age: 36

How he got his fortune: Chief Executive Officer, Ubiquiti Networks Inc

Teams owned: Memphis Grizzlies (NBA)

Championships: None

18. Robert McNair

Estimated Net Worth: $2.0 billion

Forbes 400 Rank: 273

Age: 77

How he got his fortune: Energy

Teams owned: Houston Texans (NFL)

Championships: None

Microsoft cofounder Paul Allen lives a pretty fabulous life. With a net worth of more than $16 billion, he's the 57th wealthiest man in the world, and he has the fancy yachts, planes, and lifestyle to prove it.

Allen also collects a ridiculous amount of properties across the globe. 

From a hilltop mansion on the French Riviera to an entire island off the coast of Washington, Allen has made his fair share of blockbuster purchases over the years.

Allen's primary residence is a 10,000-square-foot waterfront home on Mercer Island, a ritzy enclave of Seattle. He owns a total of nine mansions on the island, including one that's just for his mother and another that houses a full-size basketball court, swimming pool, and fitness center.

Source: Curbed Seattle, The Real Estalker

He bought Allan Island, off the coast of Washington, in 1992. Though he initially had plans to build a dream home on the island, its secluded nature and lack of electricity made construction difficult. He sold the island last year for a discounted $8 million.

Source: Curbed Seattle

In 1993, Allen purchased a former sheep ranch in Tetonia, Idaho. For years, the property operated as the Teton Ridge Ranch, a five-suite luxury mountain lodge. It closed for business in 2009.

Source: The Real Estalker