For me, or in particular for my family, my sister was the 'groundbreaking one' who a) game out as being lesbian (after a chauvinistic guy proposed to her by saying she didn't need to finish college and could just be his wife at home) and then later go back to being dominantly lesbian but with some male 'play partners'; b) being involved in the BDSM lifestyle with some of her partners. When the 'freaky goth boy who wears makeup and listens to metal, goth and industrial music' said he was into the BDSM lifestyle, it came as no surprise, nor was I shunned for it.
About anything I have 'come out as,' I have told my mother, who inevitably has told my father, but we (my father and I) have a strange relationship where we don't talk much. We aren't at odds with each other, but unless we have something to share that is "nifty cool technology related über-geeky" stuff, we just don't really talk.
One thing that was ... interesting ... to come out about was being poly. After a decade-long relationship with my now ex-wife, which ranged from being friends on first meeting (she was girlfriends with a friend of mine from college at the time) back on New Years Eve 1999, getting together in a relationship in 2001 after my girlfriend at the time left me for another man, getting married in 2006 and then divorced back in February, our relationship went through many variations. It had times where we were exclusive/monogamous, we had an open relationship where we could have any other relationships and not worry about telling anything about them, going back to monogamous, a variety of something I call 'poly-fidelity'* that was a cross between that and partner swapping, and back to being a truly open relationship.
The hardest part I had for telling my parents, is that I had waited for so long, that I didn't want them to get the wrong idea when the longest relationship was having problems, and for them to say "oh well if you didn't have that other girl on the side then you could focus on fixing the problems." They seemed to have taken it rather well, but it was still kind of awkward for some of my family to have both partners with me at family functions like Thanksgiving or Christmas.
I think that my mother had a harder time with the fact that, in order to put all the back story behind it I emailed her about legally changing my name instead of telling her in person...
- Poly-fidelity I like to define as basically having a relationship between two couples (or partners, etc), where you have a meaningful relationships outside of the initial, primary, etc, relationship rather than having an open relationship just be an excuse to be a swinger. In this particular case, there were friend relationships between everyone, and sexual relationships between everyone except for me and the other guy. We were both not into guys, so were perfectly happy just to hang out when the girls had their time alone.