1. Timelapse video showing all known nuclear explosions from 1945-1998 by Isao Hashimoto
http://www.youtube.com/watch?v=LLCF7vPanrY2. Hiroshima memorial project
http://www.openculture.com/2011/07/hiroshima_bombing_remembered_with_google_earth.html
...and the Google Earth layer that goes with it
http://hiroshima.mapping.jp/ge_en.html
3. Ground Zero simulator - pick a location and nuke it
http://www.carloslabs.com/projects/200712B/GroundZero.html