Cheat Menu:
Hold R2, L1, and Left on the D-Pad and then press start to open a cheat menu.

Cheat Menu 2:
Hold down R2, L1, Left on D-pad, R3, and then hit start. It will give you another cheat menu.

Infinite Gold or Duplicate Items:
Have 2 players playing at the same time. You need to be in town for this. Then have one character drop all their stuff. Import the character that just dropped their items and they will have all the things that they just dropped but, it's also on the ground. Pick up the stuff sell the duplicates and save. You now have more money. Buy expensive items with your extra gold and repeat this cheat again. The more times you double yor items the more gold you get each time.

Single Player Duplication:
You don't have to be in two player mode or in a town to duplicate items.You should be at a save point. 1. Save your game 2. Drop anything or everything you want to duplicate. 3. Import your character from the save in step 1. 4. Pick up the stuff from the ground. That is it.. I have done this in almost every level of the game where there is a save point. Works in one or two player games. Great way to share stuff with a friend in two player mode. Find someone who has finished the game and have them import their character into your new game, and give you their onyx sword!

Power Player:
Press and hold R2 + L1 + Left + and then tap R3 while in the game. If your character speaks, the code has been confirmed. You should now have a level 20 character with access to every feat, and level 1 feats on all class-dependent feats plus 75,000 gold pieces.

Level 20 Character and 75000 Gold:
When in play mode, press L1, R2, , Left D-Pad, R3 and start at same time to instantly make your character 20th level, with 75000 gold, 1000 Health and 1000 Mana, and a minimum of 1 in every feat, including other character specific feats. The downside is that your character does NOT gain any further experience points while playing, and is stuck at 20th level, with low level feats. The normal character max is 40th level.

Unlock Gauntlet Mode and Extreme Difficulty:
Beat the game on normal difficulty setting with any character to unlock The Gauntlet Mode. After defeating Gauntlet Mode you will open up the extreme difficulty level.

Play as Drizzt Do'Undren:
Choose 'new game' at the main menu, then hold R1 + R2 + L1 + L2 while the game loads. Alternately, beat the game on extreme difficulty.

Time Wrap:
Whenever you fight a big boss that gives you lots of experience or you find a real good item, save before you find it and then when you get whatever you want save it on a different file. Reload the frist one (before you got the item or experince) and then just import your guy from the second game (the one just after you got the item)

Experience and a Cool Sword:
Start a new game in extreme mode. Bring up the cheat menu (R2+L1+triangle+left then hit start) turn on invulnerability and then level warp to the second to last towere level. Go down the stairs to the Black Forge, then walk east to the weapon wrack and pick up the weapon then kill the metal golem who will drop the onyx sword. In extreme mode, if you were level one you should now be level 40 . In other modes if you were level one you should be level 25 or so. Also in the tower levels on extreme mode there are many chests containing powerful goodies. Remember to keep invulnerability on.

Thanks to Revolution readers Mike mathis, Scott McCutchen, MIke, and Brent James!