Empire.is features a map of more than 700 United States military bases and postings around the world. The map uses satellite imagery from Google Maps and Bing to display these bases. The map alone could be an interesting resource for a U.S. History and or current events course. (It should be noted that some of the postings on the map are closed) I would combine the use of the map with a viewing of John Green’s Crash Course in American Imperialism (embedded below).
On a related note, you may also be interested in this animation of Howard Zinn’s A People’s History of American Empire.
H/T to Google Maps Mania.