My friends at ScrewAttack have a show called "Death Battle." If you haven't been watching, the basic idea is: "Who would win?" nerd-debates + actual in-depth research + crazy-good production values, topped off with an animated short visualizing the projected result. Very much worth checking out.
Today, they've finally taken up the "versus" question that's been topping these sorts of lists for the better part of two decades now: GOKU vs. SUPERMAN. Go. Watch. Now.