Advogato

Advogato is an online community and social networking site dedicated to free software development, and was created by Raph Levien. It describes itself as "the free software developer's advocate." Advogato was an early pioneer of blogs, formerly known as "online diaries", and one of the earliest social networking websites. Advogato combined the most recent entries from each user's diary together into a single continuous feed called the recentlog, directly inspiring the creation of the Planet aggregator somewhat later.

Several high profile members of the free software and open source software movements are or have been users of the site including Richard M. Stallman, Eric Raymond, Alan Cox, Bruce Perens, and Jamie Zawinski.

Because Advogato was the first website to use a robust, attack-resistant trust metric and to release the underlying code for that trust mechanism under a free software license, it has been the basis of numerous research papers on trust metrics and social networking (see the list below for specific examples). Advogato's early adoption of an XML-RPC interface led to its use as an example of how such interfaces could be used by web programmers.

Advogato is still used as a testbed for social networking and semantic web technologies. Tim Berners-Lee, who is an Advogato user himself, included Advogato in a short list of sites that should be noted for their early adoption of the FOAF as a method of exporting user RDF URIs.