Shaun of the Dead is free card game based on the very funny movie of the same name.
horror
Reanimation Zombie Survival Card Game
Reanimation is very highly rated at Board Game Geek. And it is free.
Dice of the Living Dead
Dice of The Living Dead is a free print-and-play zombie survival horror game.
Cthulhu: The Great Old One Card Game
Cthulhu: The Great Old One is a simple, free print-and-play card game.
BioSyndrome Zombie Survival Horror Game
BioSyndrome is a community created game of zombie survival horror.