Jack Dorsey has taken this title in past years, but he had a pretty interesting past twelve months. In an industry where young entrepreneurs are "fast-talking, fast-moving, fast-thinking" clichés, Dorsey has revealed that his love of cities started right here in St. Louis, that he has only just bought his first car and that he texts his mother first thing every morning (solid "local boy" cred). But back in the fast lane: He held a Twitter townhall with the president. His new company, Square, is poised to totally upend how we buy and sell things — really, our whole relationship with money. He's been called Steve Jobs' "spiritual successor." Oh, and as of this summer, Forbes Magazine announced that Dorsey is — or is on the very edge of — becoming a billionaire. That's thanks to the latest infusion of capital investment in Square as well as his sizable stake in Twitter. Speaking of which, he's also got sort of an adorable Twitter persona. He's really into sunsets.