The Last Stand

The Last Stand is my new favorite timewaster. It's actually more of a real game than a timewaster, but it uses flash so I think it still qualifies. Anyway, you get to shoot zombies with lots of guns. And a chainsaw. There's also resource management involved, so it has a little depth beyond gunning down the brain-hungry hordes of the undead. Check it out, just not before work. (Hat tip: Joystiq)