Roger Bannister broke the mythical 4-minute mile barrier in 1954. (Source: Guardian UK)

Dean Kamen is no stranger to innovation.

He's also no stranger to doubters and skeptics. People said the Segway was impossible, but Kamen disagreed, and he was right.

"Don't tell me it's impossible," he says, "tell me you can't do it." "Tell me it's never been done. Because the only real laws in this world–the only things we really know–are the two postulates of relativity, the three laws of Newton, the