Ringworld - role-playing game - happened in 1984.
The Metabarons Roleplaying Game happened in 2001.
Pathfinder Roleplaying Game happened in 2009-08.
DC Universe Roleplaying Game happened in 1999.
Amber Diceless Roleplaying Game happened in 1991.
Marvel Universe Roleplaying Game happened in 2003.
The Lord of the Rings Roleplaying Game happened in 2002.
Star Trek Roleplaying Game - Decipher - happened in 2002.
Star Wars Roleplaying Game - Wizards of the Coast - happened on 2007-06-05.
Larry Niven wrote Ringworld.
Ringworld was created in 1970-10.
The Ringworld Throne was created in 1996.
The Ringworld Engineers was created in 1980.