Just type the following codes during the game to get the cheat.
TRIFIR0 Temporary Invincibility.
TRIFIR1 Reloads PAC.
TRIFIR2 Reloads ION.
TRIFIR3 Reloads RTL.
TRIFIR4 Reloads MAM.
TRIFIR5 Reloads SAD.
TRIFIR6 Reloads SWT.
TRIFIR7 Reloads DAM.
TRIFIR8 Recharges afterburner fuel.
TRIFIR9 Invisibility.
TRIFIR10 Full Invincibility.
TRIGODS God mode plus weapons powerup.
TRINEXT Jumps to the next level.
TRISHLD Restores shields to full strength.
TRSCOPE Oscilloscope.
TRIHOVR Combat hovering.
TRFRAME Frames-per-second.
TRIWARP# Warps to level number you type in at #.
TRIBURN Super afterburner booster.
3DREALM Weapon power-ups.
Hidden Planet:
To get to the hidden planet (planet 0), at the log-in screen enter "Terminal" as your name and "Reality" as your call sign (caps are important).