When you are at the Main Menu (it should say Capmaign, Multiplayer, Zombies and Options) start pushing RT and LT really fast. You should get out of the chair, and you can walk around. Go behind the chair that you where in and there should be a little old-fashioned computer. Walk up to it and hold X, then enter the following codes.
Code: "3ARC INTEL" then "YES"
This unlocks all Intel NOTE: when enabled you cannot earn the achievement for finding all intel in Campaign
This unlocks the "DEAD OPS ARCADE" after unlocked it can be selected in the "choose map" in zombie menu
This unlocks the Zork (The Great Underground Empire) text-based adventure game
Code: "HELLO SAILOR"
This unlocks Zork I: The Great Underground Empire (an incredibly great text adventure from 1980)
This displays a list of system commands in the terminal and Pentagon user e-mail access
Code: "CAT [filename]"
This opens the corresponding file
This displays a list of audio files and pictures for use with "CAT" command
This displays a list of login names for use with the "RLOGIN" command (requires passwords)
This gives a strange message ("Fee Fie Foe Foo!")
This loads "Alicia", a virtual therapist
Code: "RLOGIN DREAMLAND"
Remote login to Dreamland server using username/passwords (see below)[/size][/color]
Login as Bruce Harris - Username: bharris, Password: goskins
Login as D. King - Username: dking, Password: mfk
Login as Adrienne Smith - Username: asmith, Password: roxy
Login as Vannevar Bush - Username: vbush, Password: manhattan
Login as Frank Woods - Username: fwoods, Password: philly
Login as Grigori "Greg" Weaver - Username: gweaver, Password: gedeon
Login as J. Turner - Username: Jturner, Password: condor75
Login as Jason Hudson - Username: jhudson, Password: bryant1950
Login as John McCone - Username: jmccone, Password: berkley22
Login as Joseph Bowman - Username: jbowman, Password: uwd
Login as John F. Kennedy - Username: jfkennedy, Password: lancer
Login as Lyndon B. Johnson - Username: lbjohnson, Password: ladybird
Login as Richard Nixon - Username: rnixon, Password: checkers
Login as Richard Helms - Username: rhelms, Password: lerosey
Login as Richard Kain - Username: rkain, Password: sunwu
Login as Ryan Jackson - Username: rjackson, Password: saintbridget
Login as T. Walker - Username: twalker, Password: radi0
Login as Terrance Brooks - Username: tbrooks, Password: lauren
Login as William Raborn - Username: wraborn, Password: bromlow
Rlogin to Dreamland as Robert Oppen: Username: roppen, Password: trinity
Rlogin to Dreamland as Vannevar Bush: Username: vbush, Password: majestic1