ok, I've placed a little chatroom at
http://brainmeta.com/chatroom/index.php. Granted, it's not super high-tech, but it works and it has potential. I've also placed links to the chatroom on the top navigator in the forum (next to the Search link), and also on the right navigator on the main site. I have the chatroom set-up now so that you must be logged in to make a post (though you don't need to be logged in to read the posts). I did this to prevent any attempts at mimicking or cloning other people. Currently, you cannot see who else is in the chatroom, but I will likely change this in the near future because such information would be nice to know.
Also, I think it would be interesting to have private chat sessions in which you can choose exactly who you want to talk to, with no-one else being able to see the conversation... though I will have to look into this more.