No More Room in Hell? Come to Steam!
You know what? I'm starting to wonder if Valve actually tailored the Source Engine to be partial in accommodating games about zombies. Think about it, Half-Life 2 had Ravenholm, Counter-Strike: Source has special servers about fending off zombies, obviously there's Valve's own Left 4 Dead and now we have a new, standalone, mod in the form of No More Room in Hell.
The trailer makes it look rather clichéd and mechanically uninspired, but then again how's that any different from the current AAA and indie landscape? The modders appear to have put quite some effort into it and modders in general have been making some great headway into turning out to be fine game developers in their own rights.