Secrets
These can be bought in the Secret Menu

Effect - Code

Audio Commentary - 5 Precursor Orbs after buying scene players 1-3
Bad Weather - 5 Precursor Orbs After Act 1-1
Big Head Mode - 3 Precursor Orbs After Act 1-1
Blaster Damage Upgrade - 6 Precursor Orbs After Act 1-9
Dark Jak Invisibility - 25 Precursor Orbs After Act 3-11
Fast Movies - 5 Precursor Orbs After Act 1-1
Hero Mode - 5 precursor orbs, after finishing the game
Increased Blaster Gun Ammo Capacity - 4 Precursor Orbs After Act 1-17
Increased Peace Maker Ammo Capacity - 4 Precursor Orbs After Act 2-19
Increased Scatter Gun Ammo Capacity - 4 Precursor Orbs After Act 1-17
Increased Vulcan Fury Ammo Capacity - 4 Precursor Orbs After Act 1-24
Invulnerability - 100 Precursor Orbs After Act 3-11
Jak 3 Model Viewer - 2 Precursor Orbs After Act 3-11
Jak And Daxter Model Viewer - 2 Precursor Orbs After Act 1-24
Jak II Model Viewer - 2 Precursor Orbs After Act 2-25
Level Select: ACT 1 - 5 Precursor Orbs, buy it after Act 1
Level Select: ACT 2 - 5 Precursor Orbs, buy it after Act 2
Level Select: ACT 3 - 5 Precursor Orbs, buy it after Act 3
Mega Scrap Book - 2 Precursor Orbs After Act 3-11
Mirror World - 5 Precursor Orbs After Act 1-1
Peace Maker Increased Radius - 6 Precursor Orbs After Act 2-19
Rachet And Clank Gun Courses - 6 Precursor Orbs After Act 2-12
Scatter Gun Rate-Of-Fire Upgrade - 6 Precursor Orbs After Act 1-9
Scene Player Act 1 - 2 Precursor Orbs After Act 1
Scene Player Act 2 - 2 Precursor Orbs After Act 2
Scene Player Act 3 - 2 Precursor Orbs After Act 3
Scrap Book - 2 Precursor Orbs After Act 1-24
Slow Movies - 5 Precursor Orbs After Act 1-1
Small Head Mode - 3 Precursor Orbs After Act 1-1
Toggle Jak's Goatee - 2 Precursor Orbs After Act 1-1
Unlimited Ammo - 50 Precursor Orbs After Act 3-11
Unlimited Dark Jak - 50 Precursor Orbs After Act 3-11
Unlimited Light Jak - 50 Precursor Orbs After Act 3-11
Unlimited Vechicle Turbos - 30 Precursor Orbs After Act 2-25
Upgrade Vechicle Toughness - 15 Precursor Orbs After Act 2-14
Vulcan Fury Damage Upgrade - 6 Precursor Orbs After Act 1-17

Easy win on Hang Time challenge
In the mission when you must get a high hang time. In stead of doing it the standard way by using jumps in your buggy, get out of you buggy and use the mass invertor it will get you an automatic gold in total hang time (you may have to use the gun more than once) and single hang time.