Cheats for Star Wars: The Force Unleashed II for PSP

AJP400 - Unlock General Kota costume
GUNRAY - Unlock Nemoidian costume
HAAZEN - Unlocks the Sith Acolyte skin
HARPER - Unlock Scout Tropper costume
HOLODROID - Unlock Sith Training Droid  costume
MANDALORE - Unlocks Boba Fett skin
MAREK - Unlocks Force Repulse ability
MORGUKAI - Unlocks Saber Guard skin
NOMI - Unlock good apprentice costume
RAHM - Unlocks the General skin
REBELSCUM - Unlocks Rebel Soldier Skin
SHADOW - Unlocks Terror Trooper skin
SOLARI - Unlocks Wisdom (White) Lightsaber Crystals / Gain extra Force points when 
defeating your enemies
SPECFORCE - Unlock Revel Commando costume
TK421 - Unlocks Classic Storm Trooper skin
TRAYA - Unlock saber throw
VENTRESS - Unlocks Dark Apprentice skin
YARAEL - Unlock jedi Mindtrick

On the first level, at the place where you run away from the gun ship, you get Force points when you stop running and die. There is a save point, so you can run and then die. Using a rubber band to hold your controller's joystick down, you can keep doing that at the save point (running to your death), and you'll just rack up the force points.

To unlock unlimited health bonus, you must collect all of the Holocrons.