August should have been a triumphant month for Apple cofounder Steve Jobs; his once written-off tech company briefly topped ExxonMobil as the most valuable U.S. corporation. But later that month he resigned as CEO to battle what most believe is his final bout with cancer. The Reed College dropout founded Apple in his garage. Jobs created the Macintosh in 1976 and was fired 9 years later after a power struggle with Chief Exec John Sculley. 

He returned to Apple in 1996. Still most of his wealth still comes from Disney, due to Disney's purchase of Pixar in 2006; as the largest individual shareholder, he owns about $4.47 billion of Disney stock.