Quake Rally
From QWiki
Quake Rally is a mod for the original Quake created by Impact Developments, namely Ryan "Ridah" Feltrin and Rowan "Sumaleth" Crawford. Both hailing from Australia, but never having met, the two of them set out to do what many people thought would be impossible, turn Quake into a fully fledged racing game.
http://web.archive.org/web/20080101222524/http://www.quakerally.com/