My wonderful university has a decades-long tradition of the Naked Quad Run. Basically what happens is that over a thousand people get drunk and let their inhibitions fly out the door, and run naked around the residential quad for however long they want. I'm a senior now and have done it once to do it, but this year I'm out because it's raining nasty in Medford.
Apparently this began by a group of male students protesting that their dormitory was about to be turned coed - how stupid they were then - and since then has happened the night of the first reading period day.
While this year I'm out, I do plan on going out, having a little fun, and watching many of my very close friends run butt-naked and having a great time for it.