Founder and CEO, MercadoLibre
Rank change: New
In 1999 the Argentine B-school student built an early Internet lead in Latin America, founding online marketplace MercadoLibre; eBay bought an 18% stake in 2001. Since its 2007 IPO, its stock has climbed 127%; revenue grew 26% last year. Galperin's online platform competes with eBay's PayPal, which may be an issue going forward, especially with 43 million registered users and counting. But the 52,000 Latin Americans who now get most or all of their income selling products on the platform aren't complaining.
Good sport: Galperin played junior national rugby in Argentina.
NEXT: 11. Greg Jensen
Last updated October 14 2010: 1:25 PM ET