26. The system of claim 8 , where the at least one weight assigned to the at least one document reflects an amount of preference for the at least one document by the user or the group of users.
8. A system, comprising: a computer-implemented interface to receive a search query from a client device associated with a user; and a computer-implemented processing unit to: initiate a search of information regarding a corpus of documents, based on the search query, to identify a ranked set of search result documents, identify a first set of documents, each document in the first set of documents being ranked higher than a threshold by a global document ranking algorithm, identify a second set of documents, associated with preferences of the user or a group of users that includes the user, from a query history or document browsing history associated with the user, generate an intersection set, documents in the intersection set being common to both the first set and the second set, identify at least one document in the intersection set that includes a link to a particular document in the ranked set of search result documents, re-rank, in the ranked set of search result documents, the particular document based on at least one weight assigned to the at least one document, to identify a re-ranked set of search result documents, and provide information associated with the re-ranked search result documents to the user.