This term, specially cherished by American hackers and explained here for the benefit of our overseas brethren, comes from the Warner Brothers’ series of “Road-runner” cartoons. In these cartoons, the famished Wile E. Coyote was forever attempting to catch up with, trap, and eat the Road-runner. His attempts usually involved one or more high-technology Rube Goldberg devices — rocket jetpacks, catapults, magnetic traps, high-powered slingshots, etc. These were usually delivered in large wooden crates labeled prominently with the Acme name — which, probably not by coincidence, was the trade name of a peg bar system for superimposing animation cels used by cartoonists since forever. Acme devices invariably malfunctioned in improbable and violent ways.