Mine had to be attending the game where Lookingbill drained that brick 3 pointer to beat Michigan in the closing seconds. Before the game, my old man kept on saying how he was going to take a leak in the gas tank of this one Michigan van that was full of scUM fans who were talking smack to him at a football game a year or two earlier and how he knew exactly which van it was. Though I was probably too old to do so, he hoisted me up on his shoulders to scan the parking lot for the van, but I couldn't find it. To this day, he says he has a perfect mental picture of the van and he will still take a whiz in their gas tank if he finds it.
A close second is the day of the OSU game back in ought four when we were at a tailgate and my buddy was raving about how he made this awesome pot of chili. My old man takes one taste of it and announces to everyone at the tailgate that it was just some Hormel chili that had been souped up. My buddy denied and denied, but then later that day says "Man OK4P, I don't know how your dad figured out my chili was just dressed up Hormel chili." Some people know wine, others know beer and others know cigars, but my old man knows a thing or two about quality chili.