When the game is loading and you can read your "mission" randomly press buttons (Left Analog-stick, L, R, A, B, X, Y, White, Black) and you just may unlock a cheat message at the bottom left corner of the screen. Some examples include Kill All (All bot cars are disabled), Bot Gang Up (Bot cars always pile up), Monster Tires (self-explanatory), and Tiny Cars (RC cars).
Please submit any information regarding the exact buttons for these codes..