TORCS
The Open Racing Car Simulator
TORCS is a 3D racing cars simulator using OpenGL. The goal is to have programmed robots drivers racing against each others. You can also drive yourself with either a wheel or keyboard or mouse. TORCS is available on Linux and Windows. Choose from 17 different cars, 21 tracks, more than 20 opponents to race against. Graphic features lighting, smoke, skidmarks and glowing brake disks. The simulation features a simple damage model, collisions, tire and wheel properties (springs, dampers, stiffness), aerodynamics (ground effect, spoilers) and much more.
http://torcs.sourceforge.net/