I've done one such sitting... a bride couldn't afford me to photograph her wedding, and I suggested some pictures as a wedding gift, you know... tastefully nude, and she went for it. She was quite beautiful without any clothes on, and it was fun to do... did it in my studio so she could keep it a secret. Simple light, simple background... just beautiful skin, mostly, in the the pix.
I have wondered how to promote something like that... I have a website with lots of children, so I was thinking it would have to be a separate website, but word of mouth works well for any sort of personal photography jobs. And the intimate nature of the shoot... I don't know, I didn't want to ask her to sign a release, and plaster her pictures all over the web. I think discretion at times, can be a good thing.
Though there are plenty of exhibitionists out there!