I know a guy called John who got his revenge on a co-worker (can't remember what the co-worker did wrong) by using a novel approach.
The guy had a VW Beetle and one day John went down to the parking lot, removed one of the rear hubcaps and placed a large haddock and a coin inside, then replaced the hubcap.
The guy with the Beetle was puzzled because at low speed there was a knocking sound coming from the rear of the car (the coin banging inside the hubcap) but as the speed increased, the cenripetal force would stop the coin from banging and the noise would go away. Also, this noise was not detectable when examining the stationary vehicle with the engine exposed :-)
Anyway after two weeks of this knocking irritation the guy finally worked out that the sound was coming from the rear of the car, on one side. He got some mates to run next to the car (he couldn't afford to take it in to a mechanic) and they told him that the noise was definitely coming from the left rear wheel. So he removed the hubcap to have a look and almost passed out because the smell of the rotting haddock just hit him all at once. It had coated the inside of the hubcap and was really bad! :-o
Apparently he suspected John did it and he was much nicer after that.
