Want to spend some online-web-conference-screencast, but have not found suitable instruments. Skype optional, in principle, it just does, apparently, often used for such purposes. And need the following:
1. Broadcasting, voice conferencing of several people
2. Broadcasting a piece of the desktop (in the extreme case, the entire desktop)
3. Chat (for questions and comments of the audience with the possibility of a ban), with the preservation of history and time
4. Video saving piece of screen (2) voice (1)
There seems to be all.
Asking for help in the search.