What do YOU do as Staff Assistant?

[Nnystyxx]

Title says it all. What kinds of chicanery have you gotten up to in times where you had no real duties? What kinds of gimmicks or ways of annoying or disturbing the populace have crossed your mind, and how do people tend to react?

My current favorite thing to do is get a lighter and some cards, then the wizard/DM ensemble from the game room near botany, and start yelling 'FIREBALL' as I throw flaming playing cards at random objects like loose papers and bins.