I was bored tonight so was browsing around aimlessly on the net. I came across the wiki page for Pac Man, one of the first games I remember having (for the atari 2600) when I was a kid.
I was surprised to read that the game was originally called Puck Man but Midway changed the name to Pac Man because they were concerned that vandels would scrub out a part of the P and make it look like an F to make Fuck Man (how cool would it be if he was called Fuck Man!!!).
So if you ever come across a Puck Man machine, you now know that it's probably not a fake. Infact, it's probably worth a lot of money :)