Ray Kurzweil, 59
Inventor, recipient of the $500,000 Lemelson-MIT Prize, the most prestigious cash prize for invention in the United States

To jostle his ingenuity, Kurzweil uses a technique called lucid dreaming. Right before he drops off to sleep, he reviews the specifics of a problem—the background, options, context—until they become embedded in his dreams, a state where taboos relax and the rules of logic evaporate. At the first glimmer of consciousness, he's trained himself to return to the problem. "I am still in the dream, but I have conscious thinking as well so I can direct the dream," he says. "I have access to all these new creative links that I made while I was dreaming about the problem, but I also have my rational faculties. Within 15 or 20 minutes, I will typically have new key insights."