ZOMBIES!!!! A kick butt board game by Twilight Creations. It involves some very simple rules and a modular board that creates a new city every time you play. There are also a bunch of expansion packs that add new city map tiles, or rules, or story lines. Myself, my wife, and several of our good friends try to meet up every couple of months and have a night of it.
Also "Zombie Flux". It's like a Zombie version of UNO. Also much faster paced. ZOMBIES!!! is a few hours and requires a decent sized table or flat surface.