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Pierre Omidyar, eBay
Pierre Omidyar, eBay

Unlike many on this list, Omidyar's business position has remained virtually unchanged since July 5, 1999, when, at 32, he was the founder and chairman of eBay. In our article primarily about Meg Whitman, whom Omidyar and partner Jeffrey Skoll had just brought on a year earlier as CEO, Omidyar is described as the web whiz that "now just gets paid to think."

eBay had just gone public, and the surge in its shares following the IPO yielded big rewards for Omidyar, whose net worth was valued at $6.7 billion. Today he's valued at $5.2 billion by Forbes, but that isn't exactly chump change, and his eBay baby (#267 on our Fortune 500 list, up from #303 in 2009) continues to thrive under relatively new CEO John Donahoe.

Like Gates, Omidyar soon felt a need to share his riches. In 2004, he and his wife created Omidyar Network, which gives grants to innovative start-ups and non-profit organizations.

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Last updated December 01 2010: 6:26 PM ET
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