The David Rumsey Map Collection is a collection of more than 20,000 historical maps documenting places throughout the world. The maps can be searched by area, by time period, or by cartographer. You can also browse the collection using the LUNA Browser which operates within Firefox, IE, and Safari. For the Second Life users out there, the David Rumsey Map Collection can be viewed in Second Life. The David Rumsey Map Collection also offers Google Maps and Google Earth layers displaying selected maps.
Thanks to Ernie Easter for the link via Facebook and Twitter.
Applications for Education
The David Rumsey Map Collection could be an excellent resource for history and geography teachers. Students could view the historical maps and compare them with current maps. You could also use the historical maps to supplement a history lesson about exploration.