Released as the B-side of "I'm Sorry", "Calypso" received substantial airplay, enabling it to chart on the Billboard Hot 100. After "I'm Sorry" fell out of the #1 position, "Calypso" began receiving more airplay than "I'm Sorry," thus causing Billboard to list "Calypso" as the new A-side. Hence, "Calypso" is itself considered a #2 hit on the Hot 100.
John Denver was a close friend of Jacques-Yves Cousteau. Calypso was the name of Jacques Cousteau's research boat that sailed around the world for oceanic conservation.
A filk song exists in Star Trek fandom (and has been quoted in Chapter 8 of Diane Duane's Star Trek novel The Wounded Sky), based on John Denver's "Calypso," but adapted to the voyages of the Enterprise: "To sail on a dream in the sun-fretted darkness, to soar through the starlight unfrightened alone...."
Additionally, Tom Smith wrote parody lyrics for the song, which he titled "Callisto," referring to a sexual desire for Callisto, originally a villainess in the TV show Xena: Warrior Princess and then one of Xena's enemies. After Callisto was redeemed in the Xena stories, he wrote an extra verse and a variation on the refrain that attacked her for having stopped being evil. In the episode entitled ""Molly's Out of Town"" of Mike & Molly some of the characters sing Calypso while they are on the roof of a house.