GNU Audio and Video

Here you can watch video or listen to audio recordings of speeches and other events related to the Free Software Foundation or the GNU project. Video recordings are made using the Theora video codec, and audio is typically the Vorbis codec, and WebM is a new format that can be used. Modern web browsers, such as GNU Icecat 3.5 or later can play these files natively, but more information for everyone is available at PlayOgg, a campaign of the Free Software Foundation.

Source: audio-video.gnu.org