Motorheads

Supercars-mode:
In personal options, enter name: "Supercars", and team: "Grem".
The camera will now show the races from above.

Mega-springs-mode:
In personal options, enter name: "Demon", and team: "Grem".
Your car will be equipped with very bouncy suspension

LA-style suspension:
In personal options, enter name: "g-ride", and team: "west".
Play that funky music, and off you go!

Moon gravity:
In personal options, enter name: "Buzz Aldrin", and team: "NASA".
A small step for a man, a huge jump by your car.

Ignition-mode:
In personal options, enter name: "Ignition", and team: "UDS".
Not quite the same, but fun indeed.

Avenger: (Hardware acceleration only)
In personal options, enter name: "Avenger", and team: "Zx".
The map will be replaced with the Avenger sprite (from the ZX-Spectrum game).

Water Mode: (Hardware acceleration only)
In personal options, enter name: "Ramlosa", and team: "H20".

All Cars & Tracks:
In personal options, enter name: "R Peterson", and team: "Swe".

Hell Mode: (Hardware acceleration only)
In personal options, enter name: "Lemmy", and team: "Ace".

TRON-mode: (Glide only):
In personal options, enter name: "tribute to tron".
All geometry will now be rendered with hidden-line vector graphics. (Information from Cheat Machine)