BigBlueButton is an active open source web based video conferencing project that focuses on usability, modularity, and clean design -- both for the user and the developer.
Turn your slideshare presentations into webinars with one click. Seems pretty good. Presentation. video, audio and chat for free. Who needs Elluminate?
"We welcome all proposals, suggestions and ideas for the conference programme related to the main conference themes at ONLINE EDUCA BERLIN 2011. You are invited to submit proposals:"