I have a bud (Porkins and The Came From Behinds guy) who claims to only play zombie games. I tried to get him to try Prince of Persia: Sands of Time and it didn't occur to me to tell him it was a zombie game.

It got me thinking... there are a ton of zombies in games you don't think of as zombie games!

Halo Series
Half Life Series
Prince of Persia: Sands of Time Trilogy
Spider-Man Web of Shadows
Puzzlequest!
Monkey Island Series
Too Human
Call of Duty World at War

Etc...

Update:

Minecraft
DarkSiders
Deadly Premonition
Mass Effect
Fable (2)
Tomb Raider Series
Castlevania
Epic Mickey