29. A computer program product, comprising: a plurality of instructions, comprising a first set of instructions, executable on a computer system, configured to receive a search request via a user interface (UI), wherein the UI is configured to be displayed on a display of the computer system, the search request comprises one or more search terms, the search request specifies a set of repositories, the search request is a request to perform a search on a set of repositories, the set of repositories is a subset of a plurality of repositories, each repository of the set of repositories represents a corresponding type of content of a plurality of types of content, each of the plurality of types of content is in a corresponding of a plurality of formats, the UI is configured to initiate the search using the one or more search terms by communicating the one or more search terms to a search index coupled to the set of repositories via a plurality of repository interfaces, and the search index is coupled to the each repository by a corresponding repository interface of a plurality of repository interfaces; and a second set of instructions, executable on a computer system, configured to receive a plurality of individual search results from the set of repositories at a set of the plurality of repository interfaces, wherein the plurality of individual search results comprise the plurality of types of content, and a third set of instructions, executable on the computer system, configured to display, on a display device, search results corresponding to the search, wherein the search is performed on the set of repositories, and the search results are configured to be displayed in a combined format; and a computer-readable storage medium, wherein the plurality of instructions are encoded in the computer-readable storage medium.
29. A computer program product, comprising: a plurality of instructions, comprising a first set of instructions, executable on a computer system, configured to receive a search request via a user interface (UI), wherein the UI is configured to be displayed on a display of the computer system, the search request comprises one or more search terms, the search request specifies a set of repositories, the search request is a request to perform a search on a set of repositories, the set of repositories is a subset of a plurality of repositories, each repository of the set of repositories represents a corresponding type of content of a plurality of types of content, each of the plurality of types of content is in a corresponding of a plurality of formats, the UI is configured to initiate the search using the one or more search terms by communicating the one or more search terms to a search index coupled to the set of repositories via a plurality of repository interfaces, and the search index is coupled to the each repository by a corresponding repository interface of a plurality of repository interfaces; and a second set of instructions, executable on a computer system, configured to receive a plurality of individual search results from the set of repositories at a set of the plurality of repository interfaces, wherein the plurality of individual search results comprise the plurality of types of content, and a third set of instructions, executable on the computer system, configured to display, on a display device, search results corresponding to the search, wherein the search is performed on the set of repositories, and the search results are configured to be displayed in a combined format; and a computer-readable storage medium, wherein the plurality of instructions are encoded in the computer-readable storage medium. 30. The computer program product of claim 29 , wherein the plurality of instructions further comprises: a fourth set of instructions, executable on the computer system, configured to select the set of repositories, in response to the search request, wherein the plurality of repositories are configured to be specified by an administrator, the revised set of repositories is configured to be used to revise the search, the revised repository request is configured to return revised search results, and the revised search results correspond to the revised set of repositories.