Etano is a free open source project that's Unencrypted and Unencoded. That's right, you get the full source code allowing you the freedom to modify the script and customize it however you want.
Etano can be used to start up a dating site, a social networking site or any type of site involving connecting groups of people.
This is not a free 3rd party addon, but it's about the best that's available and is ideal for those seeking a professional quality chat feature to add to their Etano site that most Facebook users are already familiar with.
CometChat is Facebook style footer chat system that allows your site users to chat with each other (all online members or just only those who are connected as friends). Your users can also chat with their Facebook/Gtalk friends seamlessly in real-time from the CometChat bar. CometChat also provides a free integration module for Etano which saves money by otherwise having the need for CometChat do a custom integration.