I haven’t seen any mention of this here before, so here goes
HappyPenguin has a “Game-of-the-month”-thing going. Every couple of months they take a non-actively developed, near-finished, playable GPLed game and improve on it.
Tuxkart is the game currently selected. Originally developed on a Voodoo 1 /Pentium 133 PC, it’s a great little game although a bit buggy and the graphics could be better…
Apparently Blender can be used to create new kart models. Some have already been proposed. (See the GotM-dicussion list or the Tuxkart Support list)
Maybe someone here would like to look into this and maybe submit a model or two?
(Blender models are exported to AC3D format)