Racetrack is a paper and pencil game of unknown origins which simulates a car race in an abstract manner.
Racetrack is played on a sheet of square graph paper on which a track is drawn. Each turn a player draws the movement vector for his or her car - it can differ from the previous move's vector by only a certain amount (e.g., 2 squares total). A fair amount of planning is therefore necessary in order to negotiate curves safely.
The game has inspired many others, including:
Motor Speed
Tacara
Bolide
Triplanetary
Breakneck Blitz
Generic Racing Game
VektoRace
Grid Race