Also in a recent episode (2001), again the one with the martians and the corn circles, you might remember a bloke gets a nasty shock when he turns on the ignition in his car. Good enough. Later however, you see a flashback of the murderer describing how he killed the man. The flashback shows the man take a couple of large crocodile clips from the exhaust pipe of the car after the man gets his shock. The only problem is, the metal of the exhaust pipe doesn't connect with the ignition system very directly at all. I'm pretty sure that the only thing the bloke did was to clip the exhaust pipe, and this certainly wouldn't work.