This is a extension to the Big Blue Button video conferencing system to facilitate virtual classrooms by allowing VNC remote desktops to be shared in a video conference.
WARNING: There is no real security isolation between the remote desktops. Anybody with access to one desktop can access all desktops. The system is suitable for limited use but is not fully production-ready.
This extension itself is housed in the BrentBaccala/bigbluebutton repository. This repository contains Python support code, but is also the home of the install instructions and the issue tracker.
The extension allows different VNC desktops to be presented to different participants, each of whom is given a Linux login on the video conferencing server.
For security purposes, it's probably best to think about this extension as a login method that allows UNIX users to collaborate among themselves in video conferences.
There is also a "teacher mode" that allows moderators to observe all student desktops running in a Big Blue Button session and interact with them individually. When a student's desktop is selected (by clicking on it), that student desktop becomes full screen on the teacher desktop, and the session audio is undeafed for that student only. Pressing an escape sequence (ALT-SHIFT-Q) returns the teacher to the overview mode, and re-deafs the student.
Here's a screenshot of "teacher mode" with four students connected:
A more basic use of this software is to share a VNC remote desktop among the participants in a video conference.
For more information, see the Wiki, in particular the installation instructions.
Collaborate is covered under an open patent license.