For me I'd have to say John Roethlisberger. My old coach Thom Glielmi coached John before he coached me and he says that he's never met someone who was closer to his genetic potential than John Roethlisberger. Even after tearing his ACL in '99, Thom says John was still first guy in the gym and last one out every day. No wonder he still made the Olympic Team.
He's the man.