Dave McClure, 500 Startups

Dave McClure
If there's an early stage bubble going on , Dave McLure could be in trouble. He and his fund, the incubator 500Startups, have backed about 125 companies this year alone, fueling the dreams of hundreds of aspiring entrepreneurs with checks averaging $50,000.

McClure's model has drawn its share of criticism, but incubators like his are spotting and nurturing some gems. Y Combinator, the granddaddy of all incubators, has funded more than 380 startups in all. It claims Dropbox and Airbnb as alums--both of which scored new funding at billion-dollar valuations in 2011.

McClure himself remains a great motivator, ever-present at conferences and always pushing young people.