I saw Secretary and enjoyed it. However the protagonist is shown to have deep psychological problems and Spader's character has some serious flaws as well. This sort of implies that only psychologically damaged people are into BDSM.

I would like some day to see Polanski's Venus in Fur which is based on a play loosely inspired by Sacher-Masoch's (in)famous novella. I was tempted to see the play when it was on Broadway a few years ago but didn't. There is an Australian film called My Mistress that intrigues me as well.

Lastly I will bring up 9 1/2 Weeks. It is somewhat realistic (it is based on a woman's memoirs). I remembered that when I first saw it I had high expectations but was a bit disappointed by its BDSM element which could've been a little more overt. I found it to be a bit of a tease and not in a good way. Years later I watched it again. I still found it to be a tease but I was also disturbed by what seemed to be a vaguely antisexual tone to the last quarter of the film.