Do the following tasks during gameplay to unlock these items.

Unlockable	How to unlock
Alt. Scrap Book	Collect 200 orbs.
Big Head	Collect 30 orbs.
Hero Mode	Collect 200 orbs.
Invulnerability	Collect 175 orbs.
Jak's Goatee	Collect 5 orbs.
Level Select	Collect 145 orbs.
Mirror World	Collect 15 orbs.
Peace Maker Gun Course	Collect 105 orbs.
Reverse Races	Collect 135 orbs.
Scene Player Act 1	Collect 65 orbs.
Scene Player Act 2	Collect 95 orbs.
Scene Player Act 3	Collect 125 orbs.
Scrap Book	Collect 55 orbs.
Small Head	Collect 45 orbs.
Unlimited Ammo	Collect 155 orbs.
Unlimited Dark Jak	Collect 165 orbs.
Vulcan Fury	Collect 75 orbs.