etherkiller
Device for instantly killing computer equipment: an Ethernet jack on one side, spliced to a power cord on the other end. When plugged into an internet port, floods the computer with electricity, thus destroying it. Invented by the BOFH (Bastard Operator From Hell) from Simon Travaglia.
The IT guy was pissed off about being fired, so he took his etherkiller from router to router, frying them.