What is the greatest 4th quarter comeback of all time?

There is a lot being said about the Patriots going for it on 4th down and ultimately turning the ball over, but not much about the subsequent drive by Peyton Manning to win the game. As a person who hates Peyton Manning I still have to give him props. While no John Elway, he did add yet another comeback to his growing list. Whether you agree or disagree, tell us - what is the greatest 4th quarter comeback of all time?