So, what all have you thought about? I agree that the culture thing is true, at least because each online community I've "lived" in has had its own sets of both rules and rituals.

you know, i have to agree.....for example, here, in the spring culture, i feel free and welcomed....another site i go to is really a fan site but i don't feel so free to be myself. (the only reason i don't post my "real" name out in public here is for obvious reasons--so y'all can't find me *grin*)....i came to this site about the same time after it was created as i went to the other site. i don't post there that often because i don't feel welcome, y'know? like another fan, another threat or something. won't name the site because that's just not fair. not bashing it either, it is very helpful, there are a lot of friendly people there and it's nothing like other 'fan sites' i've ever been too. at least this one compelled me to join just because it's so informative. the folks seem to genuinely care about each other but it just doesn't seem as warm as the spring. that won't stop me from going there to add my 2-cents and stare at pics of this artist though, that's fer sure! i love it here at the spring.

What are some examples of these online communities, wer 'o land?

Let's see, I've been involved in one that produced a gaming environment, four diffrent online role-playing games, the public and private communities for the ODP, and here.