Ultimate cheat
Press L, R, L, R, X, X, Y, Y, at the main menu.

Unlimited Handcuffs
Press X, Y, X, Y, L, R, R, L, L, at the main menu.

Unlimited batarangs
Press L, R, Y, X, at the main menu.

Unlimited Batlauncher
Press Y, X, Y, X, L, R, L, R, at the main menu.

Unlock power moves
Press L, L, R, R, L, R, L, R, at the main menu.

Unlock all movies
Press L, L, X, X, Y, X, L, R, at the main menu.