[EricH]

That's a pretty standard one-- metric crescent wrenches, non-ferrous magnets, and left-handed screwdrivers (and the occasional flux capacitor) are asked for at the Pit Admin from time to time.

My favorite, though, on my team involved a dirty rubber disk of some kind. We'd hold it like it was metal and therefore heavy and tell an unsuspecting freshman, "Here, catch!" just before tossing it their way.