As with many other things, I have seen it. It is softcore by todays standards.. which brings us onto the real piece of trivia:
Marilyn Chambers is the only hardcore porn actress ever to star in a mainstream motion picture, David Cronenberg's "Rabid" from 1977.
..which has nothing to with:
The actor Tommy Berggren once went to see Ingemar Bergman in his office at the dramatic theatre in Stockholm. Bergman presented him with his latest script and gave him an hour to read it. But Berggren was so hungover that he fell asleep, and didnt wake up until Bergman came to hear what he thought about the script. Berggren panicked and stuttered the first word he saw on the script "Bach"(this referred to the score). To his surprise, Bergman jumped in delight and declared Berggren a genious because "noone else had understood that the play was in the form of a classic fugue". But Berggren excused himself and left in fear of being revealed, he did not take the part.