Cheat codes only work when you apply the Patch - 1.01.

Current Warzone 2100 Cheat Codes. Press 'T', type the code and 
hit [ENTER].

Code                Result 
time toggle       Stops and starts the mission timer 
get off my land Kills all enemy units on the map 
show me the power Gives 1000 extra power 
whale fin         Gives 1000 extra power 
hallo mein schatz Skip to next mission 
work harder    Completes all currently active research topics 
double up        All of your units are twice as tough 
timedemo         Shows frame rate and gfx engine data 
kill selected      Kills the presently selected units 
easy                Sets easy difficulty level 
normal             Sets normal difficulty level 
hard                Sets hard difficulty level 
version           Tells you when the game code was compiled 
john kettley     Toggle weather: snow, rain, clear 
biffer baker    Units almost indestructible 
shakey           Screen shakes when units explode 


If you have trouble getting the "show me the power" cheat to 
work, you may use this as a work-around:

1. Go to the savegame directory of wherever you installed 
Warzone 2100.

Here you'll see your savegame file "divided" into to small files.

2. For the savegame you want to change, choose the file with the 
".gam" extension.
example, "game1.gam"

3. Using a hex editor, change hex values 52, 53, and 54 to FF. 
Don't forget to save your changes!

4. Viola! You should now have well over 16,000,000 power! You'll 
probably only need to do this once in the game! I've done it 
once to start a new game, and have thus far encountered no 
problems--well, except that the computer won't let me build any 
more units! This combined with the "alltech.zip" cheat creates 
an almost unstoppable force!