Del.icio.us
"Social bookmarking is a way for internet users to store, classify, share and search Internet bookmarks. On a social bookmarking system or network, users store lists of Internet resources that they find useful. These lists can be accessible to the public by users of a specific network or website. Other users with similar interests can view the links by topic, category, tags, or even randomly.
Since the classification and ranking of resources is a continuously evolving process, many social bookmarking services allow users to subscribe to web feeds (see Atom or RSS ) based on tags, or collection of tag terms. This allows subscribers to become aware of new resources for a given topic, as they are noted, tagged, and classified by other users." [Read more here]
