Founder and CEO, Change.org
Almost everyone knows of Trayvon Martin, whose killing in Florida this year ignited national outrage, but few know of Rattray, the man who helped make his death a cause célèbre. Rattray's five-year-old site, Change.org, took off last year and now counts more than 20 million users, generates a jaw-dropping 15,000 petitions per month, and will bring in some $15 million in revenue this year, mostly from nonprofit advertising. Victories include persuading Universal Pictures to add an environmental message to the promotional website for The Lorax, pushing Seventeen to vow not to Photoshop out its models' curves, and enabling Martin's parents to draw 2 million signatures on a petition that even pulled the President into the ensuing fray.
Hot wheels: Rattray still drives a 1996 Toyota Camry.
Organizations headed by some of these top young minds in business have grown this past year, many of them hiring at an impressive rate. Here are seven examples.