Davis Guggenheim has directed a documentary called "It Might Get Loud," (trailer below) about rock & roll and specifically guitarists Jimmy Page, The Edge and Jack White.
At the end of an interview on The Bob Edwards Show, Guggenheim (who also directed "An Inconvenient Truth") and Edwards start talking about the next movie, the next thing to do, and they note that a lot of rock groups were one-hit or one-album wonders. I love Guggenheim's quote in response:
"The amazing thing is Led Zeppelin came back time and time and time again with music that was completely different. They kept pushing themselves. If I can do that, if I can just try to do that, just keep making interesting films, keep pushing myself, trying to do different things, even if I fall on my face, that's the thing that I live for."