1. A method in a computer system for organizing references to web pages for a plurality of users using a plurality of lists of web pages, the web pages in each list reflecting common subject matter, each list having a threshold similarity value indicating the degree of similarity that a visited page must bear to web pages in the list in order to be included in the list, the method comprising the steps of: determining that any of the plurality of users is visiting a web page; in response to the determining step: for each list of web pages: comparing the contents of the visited web page to the contents of the web pages included in the list of web pages to assess the level of similarity between the contents of the visited web page and the contents of the web pages included in the list of web pages; if the level of similarity between the contents of the visited web page and the contents of the web pages included in the list of web pages exceeds the threshold value for the list, including the visited web page in the list of web pages; receiving from any of the users for an identified list a recommendation of an identified page; in response to the receiving step: comparing the contents of the identified web page to the contents of the web pages included in the identified list of web pages to assess the level of similarity between the contents of the identified web page and the contents of the web pages included in the identified list of web pages; deriving from the assessed level of similarity a modified level of similarity reflecting the received recommendation; and if the modified level of similarity between the contents of the identified web page and the contents of the web pages included in the identified list of web pages exceeds the threshold value for the identified list, including the identified web page in the identified list of web pages.
3. The method of claim 1, further including the step of varying the threshold similarity value for one of the lists of web pages in response to user input.