Unlock All Levels 
Pause the game and press R1, CIRCLE, R1, L2, R1, L1, SQUARE 

Quick gun:
At the start of the game, run though the back door to a gun faster and safer than 
going to the man at the front. Note: Hit him in the head and he will die faster.

Better sniping accuracy:
When in sniper mode, zoom in. To steady yourself for greater accuracy, sit there 
and do not touch anything to look or move for about five secounds or until he 
stops moving around. You can now look around with perfect dead aim accuracy.

More ammunition:
Wait until an enemy reloads his weapon before killing him. Kill him before he fires 
his gun and you will get a full magazine for your weapon.

Ubisoft logo:
When you first start the FBI level, immediately after the woman shoots out your 
cuffs, go to the center of the room with the three computers. You will find the 
Ubisoft logo acting as a screensaver.

If you walk up to the computer screen, look down at it, and press X, the screen 
will say "GAME OVER".