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U2 and Jay-Z Perform In Melbourne

MELBOURNE, AUSTRALIA - DECEMBER 01: Jay-Z performs on stage at Etihad Stadium on December 1, 2010 in Melbourne, Australia. (Photo by Mark Metcalfe/Getty Images)

10 high-school dropout millionaires

Tumblr co-founder David Karp, 26, just sold his blogging platform to

Yahoo! for $1.1 billion. By doing so, he joins a surprising list of the

rich, famous and diploma-less.