The Tech 20: America's richest

It's odd to think, but Bill Gates' second career as a serial philanthropist may go down in history as having had more impact on peoples' lives than his other resume line as Microsoft's co-founder. (He remains its chairman.)

No. 3: Larry Ellison $33 billion

Oracle founder Larry Ellison continues his remarkable run guiding a company that has weathered sundry storms over the decade. (And in his spare time, he also managed to win the America's Cup)

No. 8: Sheldon Adelson $21.5

Owner and operator of the Venetian on the Las Vegas Strip, Sheldon Adelson made his first big fortune during his long run as the head of the company which ran the COMDEX trade show.

No 13: Jeff Bezos $19.1 billion

Amazon has become more than books - a lot more than books - shaking up the retail business. In the process, Jeff Bezos has proved an earlier legion of naysayers dead wrong in predicting he was trying to bite off too much.

No. 14: Mark Zuckerberg $17.5 billion

The youngest billionaire on the list, Facebook co-founder CEO Mark Zuckerberg

No 15: Sergey Brin $16.7 billion

Sergey Brin, speaking to reporters at Google I/O. — Stephen Shankland/CNET

Google co-founder Sergey Brin

No 16: Larry Page $16.7 billion

The other Google co-founder - and now company CEO - Larry Page

No 18: Michael Dell $15 billion

After briefly turning over the CEO reigns, Michael Dell came back to the company he founded. Second acts are often fraught but he's still punching the clock.

No. 19: Steve Ballmer $13.9 billion

Microsoft; screenshot by Jay Greene/CNET

Microsoft CEO Steve Ballmer, who took the baton from Bill Gates a decade ago, has had no small number of challenges trying to steer the company into the post-PC era.

No 23: Paul Allen $13.2 billion

He bailed out of the company due to illness early on, but Paul Allen's stock ownership as Microsoft co-owner made him rich.

No 39: Steve Jobs $7 billion

The zen-master of the digital age: Apple co-founder Steve Jobs. Last month he resigned as CEO because of illness, bringing to a close one of the most remarkable chapters in the history of the business annals.

No. 50: Pierre Omidyar $6.2 billion

Pierre Omidyar was a code guy who got rich when his company, which he renamed eBay, went public in 1998. Then he let Meg Whitman take over at CEO the same year.

No. 50: Eric Schmidt $6.2 billion

Google executive chairman Eric Schmidt

86 Gordon Moore $3.7 billion

You've doubtless heard of Moore's Law. That's Gordon Moore, the co-founder of Intel. A brilliant technologist and manager over a long and distinguished career, he's one of the tech industry's superstars. Whenever they talk about Silicon Valley entrepreneurship, think about this guy.

No. 91: Dustin Moskovitz $3.5 billion

Facebook co-founder Dustin Moskovitz

No. 130: David Sun and John Tu $2.88 billion, each

David Sun and John Tu co-founded Kingston Technology.

No. 139: Jeffrey Skoll $2.7 billion

The first president of eBay, Jeff Skoll has since devoted himself to philanthropy and movie production at Participant Media

No. 171: Mark Cuban $2.3 billion

Entrepreneur Mark Cuban started off as a computer dealer. During the Internet bubble, he joined the billionaire ranks by selling his next company, Broadcast.com, to Yahoo.

No. 188: Jack Dangermond $2.2 billion

Not a household name - except, naturally in the Dangermond house - Jack Dangermond founded a geographic information software development company called Environmental Systems Research Institute. Today it's the world's largest GIS software developer in the world

No. 188: Bill Gross $2.2 billion

Bill Gross