Psi is a free instant messaging application designed for the Jabber IM network (including Google Talk). Fast and lightweight, Psi is fully open-source and compatible with Windows, Linux, and Mac OS X. With Psi's full Unicode support and localizations, easy file transfers, customizable iconsets, and many other great features, you'll learn why users around the world are making the switch to free, open instant messaging.
- Voice calls (Jingle RTP).
- Basic XMPP URI handler.
- Ability to permanently trust certificates at connect time.
- Mini command system (Ctrl+7 in chat window).
- Various bugfixes.
Internet and communication
Product page: here