This sounds a lot like the mobile phone sonar that Batman used in the Dark Knight which seemed utterly ridiculous to me and many others at the time: http://sfb

This sounds a lot like the mobile phone sonar that Batman used in the Dark Knight which seemed utterly ridiculous to me and many others at the time: http://sfblunders.wordpress.com/2008/08/07/dark-knight-sonar-phones/ http://sfblunders.wordpress.com/2008/08/07/dark-knight-sonar...