Everywhere hosts Undernet and the servers have a big capacity and are very quick. LA's usually got entry space because everyone there has the Internet, major European IRC servers are smaller and you can't always get on to them.
I've never done this chatroom malarky before. Don't really understand how it works or what you're supposed to do. But I'm awake, bored, and intrigued. Explanation, anyone?
If you go to www.mirc.com they have a page of instructions for downloading and installation of program. Follow them through and it should be fine. If you can't see channel #barbelith in the list on the server, don't worry just type it in and you'll get to it.
