1. A method, comprising: a computer system receiving, at a web site, a search request that includes a digital image; the computer system analyzing the digital image to identify characteristics of the digital image, including determining an estimated time of day for the digital image based on lighting conditions in the digital image; the computer system searching, using the identified characteristics, information specifying characteristics of respective ones of a plurality of stored digital images; the computer system selecting one or more of the plurality of stored digital images, wherein the selecting is based on a comparison of the identified characteristics and characteristics specified by the information, including the estimated time of day; and the computer system returning, via the web site, the selected one or more digital images.