Lots of good and worthy picks in these comments. Sometimes it's like trying to pick which of your children is your favorite.
For those mentioning the LSU game, Bobby Olive also completed a dramatic comeback win over Iowa on the road in 1990 (Greg Frey again at the helm). This one nearly made my list because I got so excited I ran out my front door into King Avenue and my neighbors independently did the same thing. And we stood in the middle of the street high fiving.