Love those dirthy tricks! Here's one: Duck out into the parking lot and stuff a potato up her car's tail pipe.
Hehe, done that one many a time... used to get the teachers at school often with that one. 
Here's another: When dad, Dave (the bloke mum remarried to) and I worked on this building estate, everyone was in a mad rush on Fridays to get in their cars first and be at the pub before it got crowded and busy. Well the foreman, George, was always first away and first in the pub... except the day we lifted the rear of his car and put bricks under his rear axle. Poor bugger was revving away and going nowhere... by the time he had extricated himself and got to the pub we were already on our third pints... hehe.

or LadyPirate will take care of your tail pipe!
Hopefully not with a potato... it'd be right embarrassing at the proctologist's: "And, sir, were you planning to grow more from this one????"
