July 7, 2014
One of our partners in our American Futures project, along with Marketplace radio, is the Esri mapping/geographic-info company of Redlands, California. Here are two interactive maps Esri has recently produced that I think are potential time-sinks of the instructive rather than of the "you'll hate yourself when you spend half an hour this way" variety.
URL:
http://www.theatlantic.com/national/archive/2014/07/the-power-of-mapsemdashof-the-past-and-of-the-present/374057/