Enter the following codes in Code Input (Main Menu -> Extras):
Wild Traffic: FROGGIE
Traffic is all Taxis: CABBIES
All vehicles are busses: TRANSIT
Low Gravity: PILLOWS
Double Hulk's damage abilities: DESTROY
15,000 Smash Points: SMASH15
Double power pick up's: BRINGIT
Gorilla balloons around the city: KINGKNG
Sepia-tone: HISTORY
Black and white: RETRO
Italian shorts: MUTANDA