BigBlueButton is a Web conferencing system that focuses on usability, modularity, and clean design, both for the user and developer. It implements real-time sharing of voice, Web cams, desktops, slides, and chat messages to provide remote students with a high-quality learning experience. Unlike other conferencing systems, the desktop sharing works on Mac OS X, Unix, and PC computers, and there is no hard-coded limit on the number of simultaneous Web cams.
Apache OpenMeetings is a multi-language customizable video-conferencing and collaboration system. It supports audio/video and allows you to see the desktop of any participant. It includes a whiteboard, the ability to import a variety of image formats, invitations, a moderation system, backup and language modules, private and public conference rooms, and the ability to record meetings. The project also provides integrations for Asterisk, Jira, Confluence, Moodle, Sakai, and SugarCRM, and connectors for LDAP and ADS.