I've heard of the Liberty Net.... IIRC there was some "famous" AMers that used to participate. Never heard it tho... Irb comes to mind as the name I'm thinking about.
I've checked on to the Liberty Net or some sub-variant of it and had some good discussions on certain topics, but IIRC they ended up conflicting with some other net and I had trouble finding where they went. Their web site wasn't current, but it's been a year or two.