We used to play this game driving, when my daughter was younger, and I have gotten quite hooked on it alone since then; any more goodies out there? "Rudolf the Red-Nosed Reindeer" showed up on Ebbie's Getaway recordings to two separate tunes.
Seamus also sings virtually anything to the "Marine Corps Hymn."
A related song stunt (?) which my kids liked that first-time hearers often are baffled by, briefly: I have heard Cindy Mangsen sing "Take Me Out to the Ball Game" one note off, as in "take ME out to the ball GAME, take ME out with the crowd, BUY . . ." so the last line goes "it's one TWO THREE STRIKES you're out at the old b-a-l-l g-a-m-e" and stops abruptly without the last note.
Jerry Bryant sings one of the songs from Tolkien to some other familiar tune, possibly "The Fox Song" ("The fox went out on a chilly night, and he prayed to the moon to give him light"). Anyone know what song?