Cheats:
Go through walls Glitch:
Go to a wall and Press Forward+E+Psi attack at the same time
this glitch is not working on level 1,2,3,4 because you don't have the psi attack+ yet
First Person Glitch:
Normally you can not move Forward,backward,left,right when you are in First Person Mode But if you Press Melee button+Toggle First Person button at the same time you can move forward,backward,left and right in First Person mode
Mini Game - X Space '92
This Minigame is hidden in the Madness level. It's located up on a shelf in a room that has only one entrance and no connection to the other rooms and a camera above the door and a guard in front of the door. The room is before the third checkpoint which is the fenced door that needs a keycode to open. The room is the storage room. When you're in the room use your Telekinesis to get this game. When you have it use it with any computer in this level to play X-Space '92. Once you unlocked this Minigame you can always play it through the Pause-Screen.
Online chatroom
On level 3, Experimentation, on the PC where you killed the security guard outside the elevator, open the "Front Desk" applications folder on the desktop. Then, select HyperChat. You will then be able to see what the Guard has been up to, as well as that the person who the guard was talking to continues talking and gets more worried as he does not reply.
Credits
Change the channel on the television in Starke's apartment to view the developers' names.
Crying agents
Take out the tranquilizer and shoot someone in the crotch. They will fall over and start crying.
Free Radical reference
On level 13, Conspiracy, watch the video file you made and check the email on the PC. A new comedy file will download and tell you about Free Radicals official website, www.frd.co.uk. Keep logging on for more messages.
Isolation level: Easy kills
At the very beginning of the game when the Feds are trying to gun you down with their automatics, kneel down behind the desk to the left side of the room. Psi Blast the feds. After they are shot, you can then collect their weapons for your own use.
Madness level: Bounce basketball
In the beginning of the level is a shed. In the shed is a basketball the you can bounce with your "powers".
Madness level: Freed by psycho
Just before you get to Jayne Wilde, you will move through a grid with a series of cells. You can open these cells to cause a bit of havoc. However, if you stand in an empty cell and project yourself out the door and to the switch outside, you can lock yourself in. Snap back to your body and Vettic will make a comment like "Well that was clever." Wait a few seconds and one of the psychos in the cells will run along and pull the lever, freeing you.
Mini Game - Earth Impact
This Minigame is "hidden" in the Reliance level. After you entered the building through the vents there is a room with guards and Arcade machines inside. Kill the guard playing one of the Arcades and use the Arcade he was playing. Once you unlocked this Minigame you can always play it through the Pause-Screen.