The co-founder of LinkedIn has been called "the most connected person in Silicon Valley." He's also been the go-to guy for entrepreneurs seeking angel funds, helping seed Facebook, Flickr, Zynga and others. That reputation was cemented this year when Hoffman became a bridge between the new "super angel" world -- angels who invest others' money, not just their own -- and traditional venture capitalists. In September, he helped drag veteran VC firm Greylock into the super-angel game, convincing his partners to set aside $20 million for seed-stage investing.
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