How did you come to be in fandom and what do you like about it?
The timeline goes something like this:
1995 and earlier - In typical teenage-girl fashion, I was massively fannish about various actors and shows, but had no clue that organized fandom exists -- I suppose I'd vaguely heard of sci-fi conventions and such, but I really never thought about going to such things, and I didn't have anyone other than my sister to talk to about it.
1995-1998 - Went to college, discovered the Internet. I never really did fannish stuff, though, aside from looking up fan pages on actors and the like. I was pretty active on various mailing lists, but they were writing and art-related.
1999-2000 - Discovered fanfic and fannish mailing lists. Oops. *g*
2000-onwards - Decided to try writing fanfic. Oops again!
Ever since 1998 I've been in one fandom or another, to greater or lesser degrees of involvement. A partial list of fandoms that have sucked down my brain for notable amounts of time, in something vaguely resembling chronological order, include: Ranma, Stargate SG-1, All My Children, Trigun, Invisible Man, Dragonball Z, Saiyuki, BtVS, indy comics/webcomics/small press comics, X-Men (and sundry other Marvel and DC comics), Harry Potter, Fullmetal Alchemist, Yu-Gi-Oh!, Star Trek: TOS, Forever Knight, various book fandoms ...
In some fandoms I've written fic but haven't really interacted socially; in some I've been on mailing lists or message boards but haven't written fic; in some I've administrated mailing lists or message boards. LJ, for me, has changed my style of fannish discourse by bringing it all together and giving me a central forum for posting fic and interacting socially. (I know that some of the mailing lists did that too, but they were invariably mono-fannish -- as someone who switches fandoms frequently, at least in the past, the all-in-oneness of LJ is a huge draw for me.)
At this point, it's difficult for me to imagine my life without fandom in it, since it's been a major component of pretty much my entire adult life. The majority of my social circle is composed of people I met through fandom, in one way or another (counting both fanfic people, and comics/small press/'zine people, which is its own kind of fandom). I've gained a lot of creative inspiration and honed my writing skills, and I think I've also learned a lot and gotten a lot better at discussing touchy topics with strangers than I used to be.
Thanks for asking -- it's a fascinating topic! I thought about how much detail to put into this and decided to go for the bare-bones, because really, I could practically write a book. A very dull book, and one which is probably similar to that of most online fans in most ways. :D (Aside from having started out doing original writing and THEN trying fanfic ... I gather most people tend to go the other way, so I'm unusual in that respect.)
And how did all of YOU get into fandom? What was your first fandom? I'd say my first obsessive, "read every piece of fic" fandom was probably Stargate SG-1, back when there was only a season and a half of it! I never would have guessed, when I started falling out of that fandom, that I'd fall so obsessively into its sister fandom almost a decade later.