Delicious
From P2P Foundation
Del.icio.us is a popular Social Bookmarking service, founded by Schachter, Joshua, using tags that can be shared by other users as well.
More Information
See the entry on Folksonomies
Am article on the history of Del.icio.us is at http://www.technologyreview.com/tr35/Profile.aspx?TRID=432
