Corvette - Xbox

Cheat mode:
At the title screen, hold L + R and press Up, Left, Down, Right, Left, Right, Left, Right. The word "Yeah!" confirms entry. This unlocks all bonuses.

Unlock Levels:
At the options screen, go to Change Name and enter XOPENSEZ.

Thanks to Revolution readers sweetsourpppylover, Vroom and dammit!