Tor Messenger was a cross-platform chat program that aimed to be secure by default and send all of its traffic over Tor.
Tor Messenger is not in development anymore.
It supported Jabber (XMPP), IRC, Google Talk, Facebook Chat, Twitter, Yahoo, and others; enabled Off-the-Record (OTR) Messaging automatically; and had an easy-to-use graphical user interface localized into multiple languages.