WeeChat 1.1

WeeChat is a light-weight and fast cross-platform chat client. It primarily supports IRC and runs on the console, albeit there are graphical frontends (HTML5, JavaScript, Emacs, Android). It supports IPv6, Socks5, SASL, SSL certificates and SSH, can function as IRC proxy, spell checking, 256 colors. And it's highly extensible via Python, Lua, TCL, Guile, Ruby and Perl scripts in addition to C plugins. There are extensions for Jabber/XMPP or Twitter for instance.