Discovered rather by chance, it is still in beta and looks a bit clunky—hardly a positive description… 😉
However, Jitsi impresses with its simple yet feature-rich interface. It supports SIP communication, XMPP, AIM/ICQ, etc. Voice and video can also be used.
The privacy feature is particularly interesting, allowing a secure connection to be established between two participants without difficulty—and without the usual hassles of creating private/public key pairs.
Here is the link to the project homepage: http://www.jitsi.org/index.php/Main/HomePage.
