Sometime in early 2006, Josh Greenberg, a freshman at the University of Florida, began attending meetings at a school club for budding business types. The son of an electronics repairman, Greenberg was a model junior entrepreneur. In high school he’d run a small web design business; at 17, he’d incorporated it, printing his first run of business cards. Underage, he couldn’t legally serve on his company’s board of directors, so he appointed his grandfather as chairman. Now 19, Greenberg was looking to build something more concrete.