I still can’t imagine, that some of you don’t know Stackexchange.
Stackexchange is a network of community-Question-and-Answers-Sites. Maybe the programmers of you know Stackoverflow, which is also a part of that network. It has a nice system: If there’s a site about a topic you have a question about, you can register and ask a question. You can also answer other questions, sure ;). What kind of community would that be, if everyone’s just asking questions?
For asking and answering (plus some other things), you can gain reputation. Plus, there are these nice badges (I love achievements), which you get, when you do special tasks.
Oh, and I’m there, too:
The reputation isn’t that high; but I don’t want to show you, how great I am.
There are a lot of interesting sites; at first: Stackoverflow. It’s for questions about programming … and stuff.
I’m also active at Anime.SE, a stackexchange-site in public beta. A beta is for new sites to see how many users they can gain and how active the site will be later. So if you have questions about anime & manga, just ask it there ;). Maybe you’ll meet me :D.
I’m also active at German.SE, a side dedicated to German language and usage. You can see both German and English questions there, so if there’s a question … just ask ;).
However, that was my little post about Stackexchange, maybe you find something there ;). Oh, and if you want a list, what sites are already there: A nice list about all the SE-sites :).