(nobby writes...) The following text is cunningly just cut 'n' pasted from the unofficial Carmageddon Wiki, in order to fill a space. But not for long! We will shortly be spilling the full unexpurgated beans.
Carmageddon: TDR 2000 was a port of Carmageddon: Total Destruction Racing 2000, for release on the Game Boy Color handheld platform.
The game was to be developed by Torus Games and published by SCi, using the same top-down 2D engine as the previous Game Boy game. It was touted to feature nine locations with two races and two mission levels each, making 36 levels. Twenty vehicles were stated to appear, rated by Speed, Acceleration, Braking, Strength and Cost. The physics engine and car handling were improved on from the original. Finally, there was to be a multiplayer "link mode", allowing two players to battle each other or play the game co-operatively.
At some unknown point, the game was cancelled - while there are previews and a listing on the developer's site, there have been no reviews, mentions of its release, or copies for sale. The game was at 2000's E3 expo in playable demo form.