To enable cheat mode, type JASSICA16 while playing. Press F10 by itself to restore your shields, gain all inventory items, earn $30,000 and let you buy items and weapons for free from your home base. Other options include:

F        Toggle playing grid
Alt-F10  Invincibility
Alt-F7   Alternate grid
F7       Another alternate grid
Ctrl-L   Display stats
Ctrl-V   Display game version
Ctrl-Q   Transfer display toggle
~        Toggle cheat mode
H        Hack Mover. (Hold SHIFT and use your mouse
         to drag any item.)

Add these to the command line while starting your game for a change of pace.

Code       Effect
-warp #    Warp to level #
-skill #   Set difficulty level to #
-egg 250   Weapons room cheat (must be used with -warp)
-?         Displays "You DO need help!"
-asylum    Displays "Enabling ENHANCED mode. (Not!)"
-demo      Continously loops introduction