Cel Damage

Cheat mode:
Enter ENCHILADA! as a name to unlock all cars, tracks, and modes.

Invincibility:
Enter CODY as a name.

Whack Angus:
Unlock all modes (Smack Attack, Flag Rally, Gate Relay), then win all three levels in the Desert world in each one (total of nine). After completing the last level, Whack Angus will be unlocked as a playable character. His personal weapons are throwing Butchering Knives.

Gate Rally mode:
Win once in Smack Attack mode.

Hint: Flag trial:
You have to have at least one or two of these weapons: the Helicopter and Guns, and the Vacuum. Hurry and find the Vacuum in one of the weapon bins. Go straight to the Winner's (or Flag) Circle and wait for whoever gets all four flags to arrive at the circle. Once they are close enough, just vacuum them up. That weapon will not only take their Flags, but also their weapon. After doing so, go to the "Victory Ring". When you have the Helicopter and Guns weapon, just after the lone Flags first, then take out any one else who has the last desired Flag(s) you need. Next quickly go to the "Ring", because you have a limited time with that weapon.