From PFRC Wiki
If you need an IRC client, I recommend the terminal-based irssi for linux/UNIX, Mac, and Windows. (It runs in screen, and is sweet)
If you can't be bothered to do something command line, HexChat for linux/UNIX and Windows or Pidgin for Windows and linux/UNIX also supports IRC.
Configure your client to connect to the server lug.mtu.edu, then type /join #pfrc. (If you're looking for the LUG's general IRC channel, type /join #mtu)