There was a rumor in the Soviet Union that The Beatles had secretly visited the U.S.S.R. and given a private concert for the children of top Communist party members. They believed the song "Back In The U.S.S.R." was written because of the concert. Actually, some fans still believe so.
It has long been speculated that the Soundgarden song "Black Hole Sun" came from the name of a sculpture in Seattle, but according to their frontman Chris Cornell the title came from a phrase he misheard on the news. The band's name did come from a sculpture.