Well, this is embarrassing, but I haven't seen any. I've watched a ton of documentaries and science shows on PBS etc., but not actual documentary films. The only one I can even remember is one on the Alamo that I saw on an IMAX screen in San Antonio. I really loved that. The Alamo is one of those moments in history I just can't get enough of. But I'm quite remiss in viewing anything in the documentary film world.