A wide variety of RPGs represent zombies in one way or another. Upon request I could supply some information about how zombies are or could be represented in various generic and/or rules-lite systems. The following are a few of the better known representations:
Promethean: The Created - New World of Darkness gameline. Prometheans aren't exactly zombies or golems, but sort of Frankenstein-ish monsters. Wikipedia entry here, review here.