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 L, R, L, R, Y, Y, B, B, Y, B.

Unlock the Technorangs:
While playing, press L, R, L, R, Y, Y, Y, B, Y, B.

Show all items:
While playing, press L, R, L, R, Y, Y, X, B, B, X, Z, Z.

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.