There are many IRC clients available. We as staff do not directly support any. We’ll help if we can but that’s about all. Some Clients are:
http://www.icechat.net/
http://www.mirc.com
http://xchat.org
http://www.hydrairc.com
http://www.kvirc.net
http://www.ntalk.de/Nettalk/
http://quassel-irc.org
http://www.thrashirc.com
Our community has dubbed icechat to be the most popular thus far.
