David Rumsey has been delighting the cartographically inclined by placing some of his own private collection of maps online for several years now, and this latest online collection is no exception. The collection contains every map contained within his latest publication, Cartographica Extraordinaire: The Historical Map Transformed, which he coauthored with cartographer Edith M. Punt. All of the maps from the book are made freely available for the web-browsing public on this fine site, and are made even more exquisite through the Insight browser, which allows visitors a great deal of control in looking at various minute details of each map. All told, there are 118 maps in the collection, including gems such as a map of San Francisco from 1852 and an exploration map of Oregon from 1845 based on the expeditionary work of John C. Fremont.