i generally like violent games, but i wish Australia would hurry up and get an 18+ rating on games, the censor ship of left for dead 2 in aus was what ruined it for me, but anyways i decided to make a list.
fallout 1, fallout tactics, fallout 3, fallout newvegas, all of the doom series, gears of war series, dark sector (managed to get an 18+ copy), postal 2, the elder scrolls 3 - 5 and some other i cant think of right now.