Aaron Fechter invented the original Whac-A-Mole game in 1971. Well...he took the idea from "some Japanese guys" who had created a creature-whacking game first, but Fechter made the mechanism work reliably by inventing an air cylinder system to power the moles and an audio-tape-driven pattern that governed the moles' timing. Also, Fechter's game used only moles, rather than a variety of animals in the Japanese game. In the video below, Fechter (who went on to create the Rock-afire Explosion animatronic band for Showbiz Pizza) discusses how he created the Whac-A-Mole and how it was then reverse engineered and mass produced by Bob Cassata. Fechter ended up buying hundreds of the games from Cassata for his Showbiz Pizza parlors.
The lesson here? Trademark your names, patent your games. I wonder what happened to those Japanese guys.
This clip is a bonus feature from The Rock-afire Explosion documentary DVD.