The UK’s Ministry Of Defence has produced a video campaign urging responsible use of social media by servicepeople and their families – lest terrorists learn their whereabouts.
http://www.youtube.com/v/6bXzU5Xe78Y?version=3&hl=en_US
http://www.youtube.com/v/hpKiIrYDLxg?version=3&hl=en_US