Free and Open Source Web Conferencing (Online Meetings, Webinars.
eFront
OCTOBER 31, 2010
While I've found Yugma to be a very useful tool for what the Yugma team likes to call "fluid collaboration," all the other apps you've highlighted in this post (as well as others) provide simple, useful, browser-based platforms for the same processes. Elluminate is a really nice tool but not open source.
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