TORCS is a 3D racing car simulator using OpenGL. The game allows you to drive in races against opponents simulated by the computer and to develop your own computer-controlled driver (also called a robot). You can use either a wheel or keyboard or mouse to drive yourself.
Once you have developed a decent Robot you can enter championship events organized by the many fans of the game. You can find out more by reading the Robot tutorial, a link to which is available by following the download tab above.
TORCS is available for Linux and Windows.