Obscurity factor: 9
For years, there was a rumor floating around Hollywood that Mae West was actually a man. In 1970, writer/director Gene Nash turned that rumor into the fictional account of film star Dinah East (Stockwell). She was a popular star in the 1950's, wealthy, successful and when she dies in an automobile accident, it's discovered that she was actually a man. The story of how she came to be who she was is told in flash backs, juxtaposed with the scandal caused by the posthumous discovery.
This film has a rumor associated with it that Mae West sued to have it removed from distribution. I believe that rumor was dispelled, but it certainly created some buzz. It's not a great film by any standards, but it is a remarkably sensitive portrait of a man living as a woman at a time when that sort of thing made you a pariah. There is lots of nudity in the film - both male and female, which gives it an exploitative quality, earning it an X rating, but there's some meat on the sensationalist bones as well.
This film is available on DVD in two separate releases. The trailer above is uploaded to YouTube by VictoriaWarrior.
Obscurity factor: 9 (available on DVD, mostly unknown except by a handful of cult followers)