A Kiss At The End Of The Potato
One of my wife's colleagues is using A Mighty Wind in one of her music classes, which is awesome. (Wonder if she uses This Is Spinal Tap too...)
Looking at the writing credits on my soundtrack CD, I wasn't surprised to find that the principal actors themselves (in various combinations) wrote all the songs (as with Spinal Tap). The writing combinations overlapped with the performing ones, and I was amused to find that the same pair (M McKean and A O'Toole) were responsible for both the silliest (if annoyingly earwormy) song in the film and the most beautiful (which was nominated for the best song Oscar). If you can't tell which song is which, please seek medical advice.