In the main menu in the "extras" option, input these codes to unlock the following.

Password - Effect

ONFIRE - Ball trails always on. NOTE: Only affects Quick Play Mode.
BOUNCY - Beach Ball. NOTE: Only affects Quick Play mode.
PIPPED - Double unleash icons. NOTE: Only affects Quick Play mode.
CHAMPS - In Campaign mode, highlight a team but do not select it. Stay on the menu and press Square(2), Triangle to instantly win against the selected team.
NOTTIRED - Stamina disabled. NOTE: Only affects Quick Play mode.
CLASHY - Super Clash Mocde. NOTE: Only Affects Quick Play mode.
BIGDOGS - Super Unleash Clash mode. NOTE: Only affects Quick Play Mode.
CHUWAY - Two player co-op mode. Enter this code in the "extras" option.