That's hilarious.
I can't think of any off the top of my head...
A couple years ago, our swim team was on a camping trip. We were having a bonfire, and this girl and I just kinda left to go hook up when no one was looking. The girl's parents were there though, and I guess they were like where did they just go...my genius friend responds "Mike has restless leg syndrome, and they are just going to get his medication. He needs someone to go with him in case it gets too severe and he can't make it." Good one buddy, thanks.