To unlock a few extra achievements, go to the menu screen, where it shows the gameplay options, like Campaign, Multiplayer, Zombies, and Options. When you're at this screen, press and hold RS, and repeatedly press RT and LT, and you will escape from the torture chair, and unlock a secret achievement. Then look for the computer, press and hold x when you get to it, and the rest is below.
|Secret achievement||Press and hold RS & tap RT & LT alternatively|
|Gamer Picture||access the computer after escaping from the torture chair|
|Achievement||Type in DOA in the computer & wait a while on the Dead Ops Arcade Screen until you get it|
|Achievement||Type in ZORK on the computer for another achievement|