The problem with Zombie games is that you need so darn many of the things. Painting them becomes a logistical nightmare. Here’s a tutorial on a zombie speed painting technique.
Horror
Catan Horror
Catan Horror is a set of mashup rules for combining the board games Arkham Horror with Settlers of Catan.
Bump In The Night RPG
The current trend toward hybrid roleplaying miniatures game has been a lot of fun. I’ve played fun games that feature pirates, African safaris, Victorian street gangs, and of course, my own horror games tend in that direction.
Bump In The Night is a free RPG that I think could easily be modified for use as a role playing oriented miniatures game. At the very least, it has some good ideas.
Occult WWII Card Game
Occult World War II is a two player Warpspawn Card game. You need to make your own cards to play.