Five Ways to Mark Up the Web | TechCrunchIn 1999, Eng-Sion Tan and two friends launched Third Voice, a browser plugin that would let anyone make annotations on webpages. The intent was to encourage freer speech on the internet, but many slammed it as “Web Graffiti.” The company eventually shut down. The idea of web page annotation didn’t die with Third Voice, though. New services, each with unique features, have carried on. Diigo A must
