http://www.hissyfit.com is a mostly women, but not intentionally, site all about complaining about stuff. It’s pretty cool, and entertaining, until they start complaining about something you like - then it just gets weird.
I also post at http://boards.theforce.net where I give away all the secrets I know about Star Wars Episode II.
I used to post a lot at http://www.threewayaction.com but I haven’t been so much lately. Sounds like a porn site but really it’s just the combined forum for three different online journalers. (Hence “three way action”.) Except that recently one of them quit the forum, but they already had the domain name, and besides, “Two way action” sounds stupid.
People talk about just about everything there. Out of like twenty different main topics (or whatever they’re called; the equivalent of MPSIMS and IMHO) only one is directly related to online journalling.
I hang out at Fathom every so often, and I’ve been known to put in a word or two at Snopes or http://out.at/socks/ , all under the name Derleth.
A more offbeat board I don’t get around to much is a practically dead one here: IMS Talk General Chat. I was at that board when it was actually hosted by IMS (Innovative Micro Solutions), an ISP I used when I lived in SEMO (SouthEast Missouri). It is now hosted by ezboards. I’m known there as CMAN (the new software drops hyphens, I used to be C-MAN) and you can read a ‘Happy New Millenium’ post of mine, dated all the way back to Jan. 1, 2001. Yep, very slow forum. Practically dead (go to page two in the same forum to see a post by me on the topic). Ah, everything is better in black and white. 
I suppose I should plug my onw Bad Astronomy BB: http://www.badastronomy.com/wwwboard/index.html
Go there to chat about astronomy and science. Mostly it’s Moon Hoax stuff rightnow.