I've been a fan of Star Trek my entire life. Star Trek: TNG was the first TV show I liked as a child, and I spent my childhood fairly obsessed with it. I'd drifted away from the fandom over time, but recently had my interest rekindled when I started re-watching my TNG DVDs from the beginning. Turns out it really is as good as I remembered.
I also had an interesting conversation with my mom, where she pointed out that the original Star Trek was an important part of her childhood, then TNG came along and was a part of mine. There aren't many things that can endure between generations, or that are fun when you're 5 and still fun when you're 25 (or 55 in my mom's case)!
I'm mostly interested in TNG, though I like TOS as well. I have to admit I'm not crazy about most of the newer stuff.
Anyway, I look forward to getting to know you all and feeding my obsession.