I gotta say, COD3 on veteran just makes you scream. Damn snipers....

That, and it makes me ashamed to say that sometimes, on Destroy All Humans 2, I've failed loads of missions on the first few times, because it just spams you with hundreds of tanks, and sometimes you have to escort people who just insist on running head first into the crossfire, then when you die trying to protect them, or they get a disintigrator through the head, you have to go riiiiight back to the start, no checkpoints. It's not so much hard, just damn annoying....