Reanimation is very highly rated at Board Game Geek. And it is free.
horror
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.
Zombie Enclave Solo Board Game
Zombie Enclave is a free print-and-play solo boardgame of the Zombie apocalypse.