Press [Enter] while playing, then type:

Code Result

kobayashimaru - Skip to Next Mission
showmethemoney - Increases Money
phonehome - Chat List in Multiplayer Mode
screwyouguysimgoinghome - Boot List in Multiplayer Mode
canofwhoopass - 99 Additional Officers
imouttastepwithreality - ?
youstopmecold - ?
avoidance - ?

HexCheat - Invulerability:

First open the file RTS_CFG.H. Go to the line under difficulty settings and modify the line which says:

float EASY_DAMAGE = 0.5;
or
float HARD_DAMAGE = 2.0;
to
float EASY_DAMAGE = 0.0;
or
float HARD_DAMAGE = 0.0;

or whatever you want. Higher numbers make it harder. Then set the game difficulty to Easy or Hard. This will make your shields impervious to normal weapons fire. Any specials that naturally kill shields will still work.

Transport More People:

Modify the same file as above (RTS_CFG.H.) and look for the line TRANSPORTER_MAX = 5;. Change this number to something higher and your transporters will carry more people each time.

Unlimited Money Trick:

This cheat will allow any player with access to a NEBULA class starship with the GEMINI EFFECT to a source of unlimited money.

To do this have your NEBULA class parked close to a ship yard with another ship (should be a ship which can be quickly dismantled, [any of the first three classes of ships should work fine]) parked close. Fire the GEMINI EFFECT onto this ship and once it hits have the cloned ship sent for dismantling. If done quickly enough you will gain money for the dismantled ship, without losing any ships this process can then be repeated as many times as needed as a continuous source of money