2 that haven't been mentioned:
Matt Hasselbeck guaranteeing an OT victory ("we want the ball and we're gonna score")and then throwing an INT TD to Al Harris on the ensuing drive.
In Super Bowl VII, K Garo Yepremian picked up a blocked kick and frantically tried to throw a pass, only managing to whiff it up in the air where he batted it right into the hands of a defender. The he failed miserably in his "tackle attempt".
sig by BoneKrusher