Since I started at Penn State, there have been 3 losses that ended national championship runs. Minnesota in 1999, Michigan in 2005, and now Iowa in 2008. I've had the pleasure of being in the stands for two of them (Minnesota and Iowa). Each one was painful in its own way, but I think Iowa was the least painful of them all. I'd rate them this way (from most to least painful):
1. Michigan 2005. Because of the way we lost and the fact that it was Michigan. Then getting reminded of it again in 06 and 07 when they continued the streak. I think this year's win finally got me over that one.
2. Minnesota 1999. We were #2 and needed to win out to play in the title game, controlled our own destiny, etc. The game was at home and Minnesota wasn't any good. Granted, losing the next two games sort of took the sting off, but at the time it really hurt. I've never heard Beaver Stadium so quiet.
3. Iowa 2008. Obviously still painful. But the fact that we were #3 and it was on the road makes it a little less painful that the Minnesota game. It hurts but I think I would have rather lost to Iowa than to Michigan or Ohio State. Maybe 2000-2004 changed my mindset, but the fact that we still can win the Big Ten and go to the Rose makes it easier to stomach.