Elon Musk made a fortune from the Internet. Now he wants to deliver payloads into space–and save mankind by colonizing Mars. Lets get this straight: Elon Musk is not a lunatic. “I’m one of the least flaky guys you’ll ever meet,” he insists. Flaky guys generally haven’t pocketed $200 million by age 31 as Musk has, thanks to two Internet successes–Zip2, sold to Compaq in 1999 for $307 million in cash, and PayPal, bought last October by Ebay for $1.5 billion in stock.