Cheat Screen:
While in the game press Enter. Then type one of the following codes:

kobayashimaru     Skip to next mission   
showmethemoney    2000 Dilithium
canofwoopass      Ships are more independent (Greater AI)
youstopmecold     Faster Ship production
aviodence         Faster Crew Production
imouttestepwithreality  Enter Gamma Quadrant.
screwyouguysimgoinghome Boot list in multi-player mode  
phonehome         Chat list in multi-player mode 

Hints:

Fool Those Romulans:
1) When a Romulan science ship uses Holo Emiter on you, you can transport
through their shields with your holo-ed ships.

Get Money:
2) To get all the money you need; use a Nebula Class Ship (must have
Gemini Special) and a level 1, 2, or 3 ship (other ships take too long to
dissasemble). Take Nebula and use Gemini weapon on the other ship. Tell the
copy to dissasemble (make sure both ships are near shipyard before
starting) Now you will get the money and still have the ships. This is useful in
multiplayer where type-in cheats don't work.
*Note: If you select more than 1 Nebula ship, and have them both fire the
gemini at one other ship the game will freeze (not really a code but).

Neat Black Hole:
3) In the multiplayer level Junkyard, play without shroud or fog. Once
the game begins, the Premonition (future ship) falls into the black hole at
the center of the screen.