David and Catherine Cook, a brother and sister duo, started their own company under the age of 20. Their business is MyYearbook.com which is a social networking site for teens. It is like Facebook, but is geared towards teens since adults have taken over Facebook. MyYearbook.com is a player in the social-media realm. David invested $250,000 in digital aspect of it and today it is worth about $100 million!
This is truly a great idea and a great investment. I am excited to see where this company can go in the future and if it can become competition with Facebook.