Say, do you remember No More Room In Hell? It was one of the first zombie source mods announced after Half Life 2's release, way back in 2004. Cancelled twice, it still shambles on.
Tomorrow Edit: actually, 31st October - finally sees the release of the re-imagined original concept. In development for three years, this new version is going to be an 8 player co-op survival shooter. 8 player co-op! That's twice as many as Left 4 Dead. That means it's going to be twice as good. That's how it works, you know.
A meaty release trailer lurks, ravenous, in the shadows below.
How about that leaning backwards shambling pose the zombies are fond of, eh? Brr. There also seems to be a little zombie girl running around at 1:59, and that means my innate fear of small children pretty much guarantees that I'll never play this. Shame, because I always wanted to see American Psycho's Patrick Bateman and The Big Lebowski's John Goodman teaming up to fight zombies.
There's a fairly strong focus on realism on show, with one feature of the gunplay being that your ammo count is hidden from the HUD until you hold down the reload key. This will prompt your character to pull out the magazine of your current weapon and check how many bullets are left in the clip, which then makes your remaining ammo count appear briefly on the screen. I hope stuff like that will lend just enough complication to the proceedings to trip up panicking players and make fighting the horde a frightening prospect indeed, since a team of 8 gunslingers would seem to lessen the threat somewhat.