Type 'IBETYOUCANTPRINTCUNT' when in a race
F4 - Swap between ingame modes, mostly for track and car editing.
Edit mode - CHEAT

Key Effect:
1 Credits (large)
2 Peds glued to ground
3 Giant Peds
4 Explosive Peds
5 Hot Rod
6 Turbo Peds
7 Invulnerability
8 Free Repairs
9 Instant Repair
0 Credits (small)
Shift + 1 Underwater ability
Shift + 2 Time bonus
Shift + 3 Bodywork Trashed
Shift + 4 Mine
Shift + 5 Frozen Opponents
Shift + 6 Frozen Cops
Shift + 7 Turbo Opponents
Shift + 8 Turbo Cops
Shift + 9 Lunar Grav
Shift + 0 Frozen Timer
Shift + Alt + 1 Bouncey Bouncey
Shift + Alt + 2 Instant Handbrake
Shift + Alt + 3 Peds from Hades
Shift + Alt + 4 Turbo
Shift + Alt + 5 Mega Turbo
Shift + Alt + 6 Blind Peds
Shift + Alt + 7 Ped Respawn
Shift + Alt + 8 5 Free Recoveries
Shift + Alt + 9 Solid Granite Car
Shift + Alt + 0 Explosive Peds
CTRL + 1 Drugs
CTRL + 2 Gripomatic Tyres
CTRL + 3 Ped Harvest
CTRL + 4 Vesuvian Corpses
CTRL + 5 Gravity from Jupiter
CTRL + 0 Rock Springs
Alt + 1 Wall Climber
Alt + 2 Bouncey Bouncey
Alt + 3 Jelly Suspension
Alt + 4 Show Peds On Map
Alt + 5 Ped Electro-Bastard Ray
Alt + 6 Greased Tyres
Alt + 7 Acme Damage Magnifier
Alt + 8 Gravity from Jupiter
Alt + 9 Turbo Opponents
Alt + 0 Pinball Mode

On the race/car selection screen type :
KEVWOZEAR - This unlocks all races/all cars/all car upgrades
IWANTTOFIDDLE - Unencrypt all external text files. This is great for altering with the weights/properties of objects and changing the physics of the game.