The v1.06 or later patch is required to use cheats.

At the Tactical game screen, hold CTRL and type gabbi to enable cheat mode. Now enter
the following codes at the specified screen:

Tactical Screen 

ALT+E        All character and items visible
ALT+O        Kill all enemies in current sector
ALT+T        Telepotrs selected character to cursor location
ALT+D        Refresh APs of selected character
ALT+R        Reload selected character's gun
ALT+W        Select any tool from a list
ALT+B        One enemy at the cursor
ALT+C        One civilian at the cursor
ALT+I        Some random items at the cursor
ALT+Q        All buildings are explored
ALT+G        One mercenary more
ALT+Y        The robot appears at the cursor

ALT+ENTER    Aborts enemies turn
CTRL+H       Hurt character under cursor location
CTRL+U       Heal all characters

Map Screen 

CTRL+T             In travel mode, teleports squad to sector under cursor
ALT+AUTO RESOLVE   Kills all enemies in sector

Laptop Screen 

+     Increase funds by $100,000
-     Decrease funds by $10,000