I don't know if that was ever an official question, but I know we've discussed it - but that's okay, because some people are just joining in and maybe didn't answer it before.
My immediate family - my parents and my sister - know I write fanfic. My sister knew almost from the beginning because we still shared a bedroom when I started, so it was kind of hard to hide it from her. My mom knows about my site, but has never read my stories - she promised she wouldn't way back when she found out about my site, and I actually think she's kept that promise. I have to give her credit; I think I would totally snoop to see what my kid was writing, but I don't think she really cares to read stories about the Backstreet Boys, even by me. I think if she had read some of them, she probably would have mentioned it by now. She's the only one who ever asks me about my site or my writing, but it's usually with the attitude of, "Are you still doing that?? When are you going to stop writing about the Backstreet Boys and write a real book?" My dad is completely computer illiterate, so I doubt he's ever seen my site.
None of my real life friends know, and I would be mortified if they found out LOL.