Inflating one of those long clown balloons by farting into it,then making your girlfriend deepthroat it, and then popping the balloon while it's in her mouth.
Roger: Hey Chauncy, what did you do last night?
Chauncy: Oh, I gave Donna a stink lung.
Roger: Ohhhh! Did you at least give her a mint?
Chancey: Fool, hell's no! Those are MY altoids!