Heyyo,
I was just surfing the net, n' came across some interesting games/mods all invole zombies:
Rebel without a Pulse, I mean, c'mon, just look at the title, it's obviously gonna be a game aboot zombies with some comedy. It's created by bungie, and is on a soupped up version of the Halo engine, and you take on enemies that quote, "have shotguns, tanks, and all manner of futuristic weaponry. All Stubbs has is his own rotting corpse, a distinct lack of pain or conscience, and the ability to turn foes into zombie allies."
http://www.stubbsthezombie.com/
Zombie Panic is for the HL engine, and if you read it, it sounds like fun... of course, most of the time the zombie's win, but hey, I like the idea of it, n' I'm gonna dl it to play this at home. Plus, due to the basic gameplay, a bot could be easily built for this if one ain't already provided
http://www.zombiepanic.org/site/index.php?c=news
Blue Moon Rising sounds plenty sweet, it's on the UT2k4 engine, and it's a cooperative game where you kill zombies and try to beat levels. Also, since the UT2k4 engine has built-in mic support, I'd be funny to hear your buddies shreak in fear as zombies eat them alive.... well, at least I think I'd be funny.
http://www.bluemoonrising.co.uk/
I wonder if there's mods like this being made for the Doom3 engine since it already has zombies... I'll look into that another time I guess.