Toynbee tiles are linoleum tiles of unknown origin found embedded in the asphalt of streets in about two dozen major cities in the United States and four South American capitals. Since the 1980s, several hundred tiles have been discovered. They are generally about the size of an American license plate and contain some variation on the following inscription:
TOYNBEE IDEA
IN KUBRICK'S 2001
RESURRECT DEAD
ON PLANET JUPITER.
IN KUBRICK'S 2001
RESURRECT DEAD
ON PLANET JUPITER.
In the course of the film, evidence is presented that a reclusive Philadelphia resident, Severino “Sevy” Verna, placed the tiles through a hole in the floor of his car while broadcasting a message via short wave radio about his theories. ~ wiki