Bruce Lee, maybe? He seems pretty popular. He impresses me greatly but my admiration hasn't risen to the level of serious emulation, which to me is the mark of really having a hero.

My old Shihan and Sensei (two different men) from my old karate dojo (which I moved away from and haven't been back to) came closest to becoming heroes for me. While I was taking classes there, I made serious attempts to emulate these two men. I even visualized them when getting dental work done, to keep myself tough in the face of needles and drills.

Scientists, humanitarians, philosophers, statesmen, revolutionaries, soldiers, explorers, outlaws, athletes - Got any heroes?