Contributed By: Tenshi No Shi, Source: BioWare

Voice Modulation:
(Note: You need two controllers for this trick)
With your primary controller plugged into ports 1, 2 or 3 have a second controller plugged into port 4. While playign the game, press the black or white button on the second controller to raise and lower the pitch of the in-game voices.

Keep the Sith Armor :
Once you obtain the armor and complete the associated quest, equip it to another party member when you select the option of handing it over.

Keep the Sandpeople Robes:
Once you obtain the robes and complete the associated quest, equip it to another party member when you select the option of handing it over.

Easy Path to the Dark Side:
When you discover the stowaway aboard the Ebon Hawk, select the option Get out of here, whoever you are! Right now!! Then, before she leaves, talk to here again and select the same option. Continue to repeat as you gain 1 Dark Side point each time.

Fun with Bastila's Wardrobe:
Equip Bastila with dark robes and then remove them to see her in slightly different underwear.

Hidden Ending: (You need two controllers for this trick) Before the the final battle with Darth Malak press the L & R Triggers plus the Y Button on all controllers that you have plugged into the Xbox. It's recommended to have the primary controller in port 1 and another controller in port 4. This must be done before you enter the door to face Darth Malak. You'll know if you did it right if your Jedi takes out her/his lightsaber. Then open the door and walk up to Malak and talk to him.

Contributed By: Connor2k

Easy battles:
For an easy win against any opponent, target them by pushing R. Then, start running around in circles. This can be very helpful if you only have a small amount of health remaining and need to heal yourself. It can also help in a Jedi battle, as the enemy will eventually put his or her lightsaber away, giving you an opportunity to attack.

Hidden names:
When using the random name generator, press it enough times and you will get character names from the Homestar Runner cartoons, such as "Homsar" and "Kerreck." It might take a few tries to find these.

Manaan:
Sith encryption code puzzle: For these matrices: Additive: 1, 2, 4, 7, 11, 16 (19, 22, 24, 31) Subtractive: 21, 18, 16, 15, 15, 16 (14, 18, 19, 21) Multiplicative: 1, 2, 4, 8, 16, 32 (48, 52, 64, 96) Divisive: 128, 64, 32, 16, 8, 4 (2, 1, 0, -2) Exponential: 1, 32, 81, 64, 25 (1, 3, 6, 9) Logarithmic: 1 0 - 8 3 - 32 5 - 128 (5, 6, 7, 8) The answers are: 22, 18, 64, 2, 3, 7. That will get you a security card to enter the Sith Private Hanger on Manaan.