Unused Elements

These are many of the unused stuff from the game's files:

-There is a person named Durik on Sunrise W12's texture sheet

-Thunder and Thunderbull have fully-rendered trailers

-There were plenty of unused sounds in the game inculding: ambience noises, waterfall sounds, and river sounds

-There are fully made textures of a Ford Expedition, a Toyota Celica, a Hummer H1, and a Nissan 350Z.

-The Nightride level has only a few resources: level icons for the selection screen, not a lot of data for the world and environment, and the dome-modelled sky which is completely different than the one on the icon.

There is also some little-known features about the game:

-Pressing the TAB key will let you drive your opponent's vehicle, but it will crash the game

-The game has a "Free-Camera Mode." It allows full accessibility of all the tracks (excluding Nightride) and also allows you to still control the vehicle that you have selected.

C: Activates the mode. Pressing it again will return you to the original vehicle that you were controlling

W, A, S, D: Camera movement

Q, E: Controls the height of the camera

Z: Moves your camera from anywhere in the map to directly underneath the vehicle that you are controlling

SHIFT: Speeds up the camera movement

Mouse: Look around.

You can find more info here  and here