There've been quite a few. Obed got his start at witnesses.about.com. Eventually (in '98, I think), he started up his own site, witnesses.net.
Somewhere along the line, a guy called Dwayne started a site called greatcrowd.com. One of the admins there eventually left and started a small site, I don't remember the name... everyone just called it "Aisne's site." (SpunkyOne was her username.)
In early 2000 (or possibly earlier), a bunch of mods and admins from witnesses.net split because they felt that Obed was becoming apostate; they started a site called WitnessesOnline (WOL), owned by Big Ray. A nutcase called Focus ran witneses.net for a little while, made a ton of enemies, and left (or got booted) and started a site called Online Friends.
Sometime around then, the managers of the witnesses.net chat room also decided to bolt; and they set up their own chatroom, JWChat.net.
The next crop of Witnesses.net admins eventually resigned en masse in the summer of '00... some of them went on to start their own sites. (I know of one called Bently & Friends.) SpunkyOne became admin of witnesses.net
Late in '00, a few people (myself included) from WOL and Witnesses.net created a small site called JWZone. Around the same time, Obed shut down witnesses.net, and came out publicly as an ex-Witness.
Sometime, I forget when (I think in '01), the admin of GreatCrowd, Viktoria, got tired of reporting to Dwayne. She started her own site at greatcrowd.net. Eventually, that site got shut down, and was succeeded by the private site foreverfriends.us.
Late in '01, Big Ray decided to shut down WOL. A group of WOLers (led by myself) started up a replacement site called PLN.
Around the middle of last year, a group of PLNers who were dissatisfied with the restrictive atmosphere there decided to start their own site. And that's how WitnessWorld was born.
Last October, when my decision to leave the org became public, the other admins shut down JWZone in a panic. It relocated to a new URL and is now called Deep Space Zone.
There was another board in the mix, called JehovahsWitnessesOnTheWeb. I'm not sure when it was started; the owner was named Ryan, I believe.
I know there've been other groups; there was The Virtual Gathering; t-tools and greektheology; and more. But those are the ones that I had some involvement with.
Does that answer your question?