There is a comedian, Bob Rivers, who specializes in putting new lyrics on familiar tunes. I especially remember a couple Christmas albums with songs such "O Little Town of Bethleham" sung to to "The House of the Rising Sun" and "I Am Santa Clause" to the tune of "I Am Ironman" and "Walkin' 'Round In Women's Underwear" to "Winter Wonderland"
Grant Barrett said:
Ever notice how you can sing the lyrics of "Amazing Grace" to the theme from "Gilligan's Island"—or for that matter, to "The House of the Rising Sun"? Turns out there are many more examples of this. Is there a word for this musical phenomenon? (Did you know Garrison Keillor can sing "Amazing Grace" to theme song of The Mickey Mouse Club.)
Peter Schickele, creator of PDQ Bach and erstwhile host of "Schickele Mix", could sing Robert Frost's "Stopping by Woods on a Snowy Evening" to the tune of the tango classic "Hernando's Hideaway".
I was on a music team for a weekend spiritual retreat, and we decided among ourselves that we were not going to use the traditional tune for Amazing Grace, so we were trying to think of other tunes that would fit: House of the Rising Sun, Gilligan's Island, the Coke song ("I'd like to teach the world to sing"), Joy to the World, It Came upon a Midnight Clear (which I like because it fittingly shifts to minor chords right at the "dangers, toils and snares" line)...
One of the leaders came over to see what we were doing, looked at our list, then asked, "How come no one ever sings 'House of the Rising Sun' to the tune of 'Gilligan's Island'? (I almost burst out laughing.)
sing one song to the tune of another - I don't know if there is a word for exactly that, but it is based on meter, that is, the number of syllables in each line. For example, Amazing Grace is 8.6.8.6., also known as Common Meter. You can read the Wiki article at .
Back when I was into filking, the Tolkien fans discovered that most of the poetry in the Hobbit and the Lord of the Rings had the same meter as the Camptown Races. Thus, you would have
A! Elbereth Gilthoniel, Doo Dah, Doo Dah
silivren penna mÃriel, All the Doo Dah Day
Filking is a much broader that simply singing one song to another's tunes. It also covers song parodies and original music/words for the various genres of fantasy and science fiction.