Ty the Tasmanian Tiger

Bonus Level & alternate ending:
Beat the game and collect all Opals, Eggs and Cogs to unlock a bonus level and an alternate ending.

Unlock Aquarang, Elemental Rangs, Dive and Swim:
While playing, press L1, R1, L1, R1, Triangle, Triangle, Square, Square, Triangle, Square.

Unlock the Technorangs:
While playing, press L1, R1, L1, R1, Triangle, Triangle, Triangle, Square, Triangle, Square.

Show all items:
While playing, press L1, R1, L1, R1, Triangle, Triangle, Circle, Square, Square, Circle, R2, R2. 

Zoomerang:
If you collect 10 golden cogs, you will unlock the Zoomerang.

Multirang:
If you collect 20 golden cogs, you will unlock the Multirang.

Infrarang:
If you collect 30 golden cogs, you will unlock the Infrarang.