Trivia: The show is based on creator Ian Brennan's experience in show choir at Prospect High School in Illinois.
Trivia: During the Fatman cartoon, when the fish is using his charge card, a zoomed in shot of the card itself is shown. The fish's bank is noted as "DNA", a reference to the Fatman cartoon's producer, DNA Productions.
The One True King (To Unite Them All) - S2-E10
Trivia: A kid named Menken offers to write young Richard a theme song. Alan Menken was one of the composers for the series.
Trivia: After the series became a major success upon release in 2008, director Joss Whedon teased that he would be doing a sort-of "sequel" at some point in the future. At one point, an outline and a number of songs for the sequel were written, though due to other obligations, Whedon had to push back production. As of 2018, the long-rumored sequel has yet to materialize, though everyone involved has continued to hint that a follow-up may still happen eventually.