At one point, Nigel wows the crowd by playing his guitar with a violin. Musically, it doesn't quite work, but at least the creativity involved is impressive. As it happens, however, it's not as creative as you might think. This was actually a nod to Led Zeppelin guitarist Jimmy Page, who was famous for playing his guitar with a violin bow. But if Page took things to ten, then Nigel certainly took them to eleven. (Source)

Originally, Rob Reiner was slated to be just another member of the band, rather than the director of the documentary who went around interviewing them. Why did that fall through, you ask? Apparently, according to Harry Shearer (Derek Smalls), Reiner "didn't look good in tights." You know, we don't have a hard time believing that. (Source)

There was one small storyline that didn't make it to the big screen. It involved those cold sores we see on the band members' lips at one point in the film. And, uh, it has to do with, a virus carried by a certain singer that both of them were intimate with. But we don't want to herp on it. (#sorrynotsorry) (Source)