1. A system comprising: a computer configured to sort search result items based on a first clickthru popularity for each search result item and a second clickthru popularity for each search result item; the first clickthru popularity for each search result item being derived from a first number of clickthrus for the search result item that occurred during a first time period; the second clickthru popularity for each search result item being derived from a second number of clickthrus for the search result item that occurred during a second time period that is different from the first time period.