Ignoring potential energy is the source of much confusion and “inspiration” to designers of perpetual motion machines of the first kind. Simple experiments with magnets demonstrate how confusing and deceptive it can be when all energy flows are not accounted for. Fortunately, physicists, engineers, and patent examiners have learned to approach claims of “over unity” (something for nothing) with extreme scepticism. Now if we could just get the economists and politicians on board.