Empathy - Apps/Empathy - GNOME Wiki!
CoSketch - CoSketch is a multi-user online whiteboard designed to give you the ability to quickly visualize and share your ideas as images. No registration or plugins required.
Psi-IM - Psi-IM is a messaging program that is designed for the XMPP network.
Coccinella - Coccinella is a free and open-source cross-platform instant messaging client with a built-in...
IM+ - Chat everywhere! IM+ is the most widely used mobile IM app! Connect all-in-one to MSN, Yahoo!, Goo...
Conceptboard - Instant Whiteboards for Teams & Projects