Energizer Bunny

A pink drumming rabbit that started life in 1988 as a dig at a rival: the Energizer Bunny was created as a parody of the Duracell bunny. The joke then grew far beyond its target. Its cleverest phase had the bunny wander onto the sets of realistic-looking commercials for fictional products and march straight through them, so viewers spent the first seconds of every ad unsure what they were watching. That format turned the battery's selling point, that it keeps going, into a running gag about interruption, and the character has stayed in Energizer's advertising through changes of agency ever since.