Syphon Filter - All weapons and infinite ammo

Hard Mode:
At the New Game title screen press Left L1 R2 Select Square Circle X.

Movie Theater Mode:
After jumping out of the saloon window, there is an alley ahead and to the left. Go down it, and you'll be in a cul-de-sac blocked off by burning cars on the far side of the cars, some terrorists are shooting it out with some CBDC agents on the roof. You will see a movie theater across the street from the alley. Go up to the door, pause the game, and go to the Map. Press L2 R1 X RIGHT. Gabe will say, ''Got it'' Exit the menu and resume the game, and you will find Gabe inside the theater. Go around past the concession stand and enter the red-curtained door to the auditorium. The FMV movies will begin to play in succession. Warning: Some of the movies include spoilers.

One-Shot Kill:
Pause the game, highlight Silenced 9mm and press Left Select Square X L1 R2.

Stage Select:
Press Start, choose Options, then highlight Select Mission and press Left L1 R1 Select Square X.

Super ammunition:
Start the game and hit pause. Then, highlight the map menu and press: right, R1, R2, X.

Weak Enemies:
Pause the game, highlight Map and press Right L1 R1 X