WeeChat

http://weechat.org/

Links

http://www.bitlbee.org/ BitlBee brings IM (instant messaging) to IRC clients (see Hak5 YouTube channel)

Usage

From https://weechat.org/files/doc/devel/weechat_quickstart.en.html:

weechat
/set irc.server.freenode.nicks "<your nickname>"
/set irc.server.freenode.autoconnect on
/set irc.server.freenode.command "/msg nickserv identify <your password>"
/set irc.server.freenode.autojoin "#django,#saltstack"

Keys:

# switch
Alt, *left* or *right* arrow

# split window
/window splith 50

# switch windows
F7 and F8