Chairman and senior executive at IAC, Expedia, and TripAdvisor
While the stock of IAC Group (IACI), the Internet holding company Diller chairs, are essentially flat for the year, shares of his Expedia travel site have soared more than 100% this year, proving that the media mogul still has a hot hand. This year, he also paid $300 million to wrest About.com from the New York Times, and backed controversial online TV service Aereo. He was behind Newsweek's bold decision to shutter its print operations, and he teamed with Scott Rudin to launch Brightline, which aims to disrupt the book publishing industry. --Jessi Hempel
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