15. A system comprising: a processor; and a computer-readable medium comprising instructions to cause the processor to perform operations comprising: updating a computer searchable index of a corpus of resources from time to time to generate an updated index for use by a search engine to provide index search results to search queries, the search results for any search query being based on a most recently updated index; recording in a computer readable memory change data specifying changes made by users affecting resources in the corpus, including recording for each change a respective user making the change, the recorded changes occurring so late as not to be reflected in the most recently updated index; receiving a first search query from a first user and a corresponding first index search result based on the most recently updated index, wherein the first index search result comprises resources indexed in the most-recently updated index that satisfy the query; and searching the change data recorded in the memory to identify any changes to the corpus of resources made by the first user that relate to the first search query and if any such changes are found, generating a revised search result from the changes and the first index search result and providing the revised search result to the first user as a response to the first query, and otherwise providing the first index search result to the first user as a response to the first query.
15. A system comprising: a processor; and a computer-readable medium comprising instructions to cause the processor to perform operations comprising: updating a computer searchable index of a corpus of resources from time to time to generate an updated index for use by a search engine to provide index search results to search queries, the search results for any search query being based on a most recently updated index; recording in a computer readable memory change data specifying changes made by users affecting resources in the corpus, including recording for each change a respective user making the change, the recorded changes occurring so late as not to be reflected in the most recently updated index; receiving a first search query from a first user and a corresponding first index search result based on the most recently updated index, wherein the first index search result comprises resources indexed in the most-recently updated index that satisfy the query; and searching the change data recorded in the memory to identify any changes to the corpus of resources made by the first user that relate to the first search query and if any such changes are found, generating a revised search result from the changes and the first index search result and providing the revised search result to the first user as a response to the first query, and otherwise providing the first index search result to the first user as a response to the first query. 21. The system of claim 15 , wherein the corpus of resources is recorded in a table; and generating the revised search result from the changes and the first index search result comprises: searching the table for the recorded changes specifying changes made by the first user; and altering the first index search result to reflect the recorded changes.