Press the CTRL+SHIFT+S key combination. This will cause a game settings dialog box to appear. Type "cheat allowcheats" into the bottom text box followed by the "Enter" key.
Note: Cheats are allowed only in single-player mode.
Code – Effect:
cheat allowcheats - Enables Cheats.
cheat allunit - Allows you to build any unit, even if you haven't researched it.
cheat breakground - Instant contruction of facilities.
cheat e=mc2 - Causes research to be completed in one day.
Espionage succes rates increase as well.
cheat endday - Prevents the computer from doing some daily calculations (such
as "spotting"). Using this cheat will increase game speed.
cheat georgew - Adds $10 billion to treasury.
cheat instantwin - Makes you instantly win the game.
cheat nomove - Prevents units from moving.
cheat onedaybuild - All units set to be constructed will be completed the next day.
However, this also applies to the AI and can slow down the game.
cheat saddam - Random AI country will declare war on another random AI Country.
cheat saddame - Random AI country will declare war on the player.
cheat shelovesme - Increases your country's relationship with the UN to max level.
cheat shelovesmenot - Decreases your country's relationship with the UN to minimum level.