That old LOTR poster I had in College, is actually much older and comes back

 “Lord Of The Rings” poster by Jimmy Cauty (1976)

Lotsa good info here: http://klf.de/home/jimmy-cauty-solo-projects/athena-posters/

Summary: that was the most popular poster, originally from 1976 by Jimmy Cauty, and it pops back up here and there (at least on Ebay).