One of my favorite finds is Fotofun! There were two...one for regular snapshots and one which produced real photo postcards (of a sort) Both are pretty scarce. Those of you manipulating photographs might be surprised to know W. J. Glassmacher thought up the gimmick in 1934.
Pair of Treasure Chest Fotofun Novelty Photograph beheading games! Laugh your HEADS off! Collection Jim Linderman