Lee Brown, 23; Lucas Brown, 23; Lin Miao, 20
Lin Miao and the Browns (twin brothers) founded marketing firm Tatto while students at Babson College in 2005 with a $100 investment (enough to pay for the first month's Web hosting fees). Tatto's business model is simple: Businesses with lots of advertising muscle such as Blockbuster (BBI) hire Tatto to help acquire customers online. Tatto, using its proprietary technology, builds an inexpensive online marketing campaign to fulfill that demand. Advertisers don't pay for clicks or impressions; instead they pay when they acquire a legitimate paying customer. According to Miao, Tatto serves more than 10 billion impressions to over 80 million unique users every month. He says revenues are $25 million for 2007 and expects them to grow to $50 million by 2008.