http://swicki.eurekster.com/ 

Swicki is a search engine which strives to provide customized results that are more relevant than a general search on a regular search engine.  This is done by creating a Swicki, a customized directory with preferences that are specified by the creator.  A directory is initialized by filling out a survey of preferences, thereafter, search results are updated based on click patterns of all users (within a Swicki) on results of all searches to improve results and update parameters for more relevance on future searches.    Users can pick a directory to search in and results will be filtered to give links which are more relevant to target group specified by the Swicki.  Users of a specific Swicki can be referred to as a community consisting of users with similar interests.   

The site is the core of a large network of Swicki users, which can be broken down into sub-networks consisting of users with similar interests, “like-minded users”.  Users may or may not know each other.  Since members of the communities on Swicki are private and anonymous, it is unlikely that users of the same Swicki directory have a relationship with each other; however each member of a community has a dependence on the other users as they all affect the search results.  If we were to attempt to draw a graph to depict this network, with a square node representing websites that users click, circular node as users and edges showing that a user has clicked a website; we would have a graph of many circles with arrows towards different squares.  A community would be identified by a group of circles connected to similar squares; while the users are dependent on each other they do not interact and are not connected to each other on the graph!  Is there a better way to represent the communities?