From Magicpedia:
Skullo-cation is a trick by Bill Nord, first sold around 1948. The performer places several cards in the mouth of a small skull key chain. He shakes the skull and all the cards fall to the table, except one. The selected card.

Many of the original advertisements for the trick quoted John Scarne as having said, "Bill Nord's Skullo-cation is the most terrific close-up trick I've seen."