Rated X for eXciting!
Once Upon A Girl is the 1976 X-rated live action/animation hybrid that features a cross-dressing Mother Goose on trial for obscenity. Mother Goose is played by a befrocked Hal Smith (Otis from The Andy Griffith Show!), and she's forced to recount all of the nudity and sex ostensibly included in her racy stories. As she takes us deep within the tawdry worlds of Snow White, Cinderella, Little Red Riding Hood and Jack and the Beanstalk, orgies abound in and out of the courtroom.
Written and directed by Don Jurwich of Scooby-Doo and Smurfs fame, Once Upon a Girl scandalized the animation community - although according to Wikipedia's faint praise: "The film was released in some theaters and did not lose money." So that's good.