A remake of an old mod for the original Half-Life, this excellent online WWII shooter looks and plays better than ever because it is essentially an overlay on top of the heavily updated Half-Life 2. Though it's team-based, you can just join a side - you don't need to arrange one. Death in DoD: Source comes quickly. Claustrophobic. Exhilarating.
Above: You won't kill many, but at least you can dig your own grave as you fall