The Lamborghini Countach 5000 Quattrovalvole from NFS World.
No custom handling, here's my vehicles.ide line (uses Infernus handling):
countach, countach, car, INFERNUS, INFERNUS, VEH@LOW, VEH@LOW_INFERNUS, 20, 999, 0.2500, 0.2500, 0, 5, 1.0 ,0, sports
Known issues:
Doors don't work properly (NFS World doesn't have properly seperated door models, so only the outside part of the door moves)
Detached/moved components reveal huge holes in the car mesh (NFS World's cars weren't designed for IV's damage model)