Cheat mode:
Type jassica16 during game play. A voice will speak to confirm correct code entry:

Result - Code:

God mode - [Ctrl] + [F10]
Hack mover mode - H
Display framework - F
Display current location - [Ctrl] + C
Toggle CD transfer display - [Ctrl] + Q
Miscellaneous information - [Ctrl] + V
Display grid - [F7]
Display grid 2 - [Alt] + [F7]
Display grid 3 - [Ctrl] + [F7]
Full weapons, health, and energy - [F10]
Glide across floor and quick spin - [F10] + [Up], [Down], [Left], or [Right]

Ammunition refill:
Press [Ctrl] + D to drop a gun, then pick it up again. The current clip will be refilled.

Level select:
Start the game with the -warp (level number 1-15) command line parameter.

Difficulty select:
Start the game with the -skill (skill level 1-4) command line parameter.

Start game play in the bonus room:
Start the game with the -egg 250 command line parameter.