Documentaries

After a bad experience with Orson Welles' F for Fake, I showed Chris Smith's Home Moviein Advanced Writing tonight. I had wanted to show Fast, Cheap, and Out of Control but couldn't find it from the library or video stores.

Other than Michael Moore type documentaries, it's hard to find a documentary that has a clear message but Moore's are so blatant and inflammatory (at least to students) that I wouldn't use them in class. Are any others out there?