An alcoholic drink. Fill a standard shot glass 3/4 full with Cointreau. Light on fire. Slap your hand down on the still-flaming shot glass (don't wait too long or the shot glass will overheat). Make sure to keep your hand flat, and center the shot glass in the middle of your palm. The glass will suction onto your palm. Raise the glass, show your friends, then slowly remove it from your hand and drink the shot. Even better if you can inhale the air as well.
We were drunk at Rich's party last night; we drank five Cointreau Slappers each.