Achievements: With his Harvard classmate Bill Gates, Allen co-founded Microsoft and was an integral part of the company's research and product development team until 1983. Allen was behind some of Microsoft's most well-known products, including MS-DOS, Word, Windows and the Microsoft Mouse. Allen left Microsoft in 1983, after a battle with Hodgkin's disease, but chose to stay on the board as the company's second largest shareholder.
Today: Allen officially resigned from Microsoft in 2000. He remains on the board of Vulcan, the company he founded in 1986, as a way to oversee his multiple philanthropic and business ventures. In 2011, his published memoirs, "Idea Man," which chronicles Microsoft's early years, made it onto the New York Times Best Seller list. Since 1998, Allen has also founded three museums and also recently put his guitar skills to good use in the formation of a new band, Natural Born Swimmers -- whose song "Divine," co-written by Allen, made it onto the soundtrack of the movie “Magic Mike.”