Quoth the Johns:
The melody came from a ska tape I bought without any publishing credit. I recorded a MIDI version of it for the Mono Puff Hello CD of the Month Club and added the lyrics. The middle break here is all electronic music and an electric guitar plugged directly into the tape recorder. That part was smashed together at around four in the morning at Hello Studio.
John Flansburgh
[source: monopuff.org's online Unsupervised Libretto]