OoB via door + Ladder
Door OoB V1 - Press L+A or L1+X in front of any unlocked door, timing is fairly strict
Door OoB V2 - Crouch in front of any unlocked door and press A+B or X+O
Ladder OoB - Place a Proximity Mine next to the ladder, Move around (but making sure to stay near the ladder) until the Mine make a beeping noise, once you hear that making any movement will set of the Mine so press A or X to climb the ladder which will set of the Mine at the same time, knocking you off and entering the OoB state, controls will be very messed up but can be fixed by interacting with an object in the area
Memory Glitch
When you exit the game via the Game Over screen some of the game data is not cleared from the system memory, Crates that you can push/pull and certain non random puzzles will remain in their last position instead of resetting to the default location (as it would if you died and pressed 'Continue')
100% Accuracy (Discovered by Dark Harmonixer)
Normally, when shooting the Stimulator Automatic or SMG, the spread forces you to slow your rate of fire to maintain accuracy but there is a workaround for this by simply holding X or Square to override the lock on while you fire
Animation Skip [PS2 exclusive] (Discovered by Dark Harmonixer)
Simply Pause the game via the VM Menu when an uninterruptible animation is playing (Neck Snapping, Reloading, Moving Objects etc.) to regain control and save time, Does not work in VR as you cannot access the VM Menu there