"Size Matters" Ratchet Skins
First, go to the "Special" menu with any character. Then choose "Check Size Matters Save". If the game detects a Size Matters save on your memory stick, several free skins will be unlocked, and are accessible via the "Skins" menu. They will cost you no Titanium Bolts.
Activate Chalice of Power
Go to the Treehouse and enter the cheat Up, Up, Down, Down, Left, Right, Left, Right in the area where you find the Chalice.
Cheat Mode
Spend the indicated number of Skill Points to unlock the corresponding cheat option.
Big Headed Clank: 4
Big Headed Ratchet: 8
Mirrored Levels: 12
Weapon Switching: 16
Big Headed Enemies: 20
Super Bloom: 24
Old Timey: 26
Expat Exchange: 28
Bolt Confusion: 32
Pumpkin Heads: 40
Snowman Heads: 45
Kapow: 50
Ratchet Pack: 65
Hardcore Mode: 65
Zoni skin
Type the code Left, Left, Right, Up, Down, Down, X in the pause menu.