Collaborative resource on the history of computing and the Internet (GNU Free Documentation License), and the online companion to the book Technomanifestos. www.technomanifestos.net
A project initiated by author Neal Stephenson as a resource first to annotate his novel Quicksilver, but based on the broader concept of a "metaweb" devised by Danny Hillis. www.metaweb.com
Nupedia was a public peer-reviewed general encyclopedia created by volunteer scholars, with resources for readers and contributors (GNU Free Documentation License). It can be considered to be Wikipedia's direct ancestor. en.wikipedia.org/wiki/Nupedia
A peer edited encyclopedia for Linux and Open source software. The project provides usable documentation that accommodates cross references and glossaries for all relevant terms in an article. linpedia.org
A collaborative music encyclopedia. Contains melodies and musical themes from classical, popular, and folk music. Can be searched based on the melody alone, either by whistling or singing, or by entering the gross contour as Parsons Code. musipedia.org
A free encyclopedia of people, issues, and groups shaping the public agenda. It catalogs descriptions and details of PR firms, activist groups and government agencies as well as the criticisms that are made of these groups from different perspectives. www.sourcewatch.org
An encyclopedia for reenactors of the Middle Ages and Renaissance period with a heavy slant towards members of the Society for Creative Anachronism. cunnan.sca.org.au