There is this program called Tempest of Eliza. It helps you to listen your mp3 via radio. How it works is simply amazing. Back when i was in college me and my friend tried this and when i ran the program he was able to listen to the song from a radio in his room.
The principle behind this is called Van Eck Phreaking.
Information that drives the video display takes the form of high frequency electrical signals. These oscillating electric currents create electromagnetic radiation in the RF range. These radio emissions are correlated to the video image being displayed, so in theory they can be used to recover the displayed image.
This when i tried, was for CRT monitor. This now holds good for LCD screens too(its the kind of screens on a laptop). The latest research which was revealed in April 2007 confirms that it can be even done for LCD monitors too. The equipment well under $2000.
With a flat panel display the aim is to tune into the radio emissions produced by the cables sending a signal to the monitor. The on-screen image is fed through the cable one pixel at a time. Because they come through in order you just have to stack them up. And Markus Kuhn has worked out how to decode the colour of each pixel from its particular wave form
The major advantage of this technology being used is that you no longer need to be on the same network or compromise on any aspect to access information or to do a hack. Just sit and record what ever is appearing on the screen, by sitting a few 100meters away and your work is done.
Well apart from the huge security issues arising here, imagine these technologies reaching homes. You no longer can watch porn movies in your bed room … ahhhhrgggg nooooooooooooooooo
Related Reading : New Scientist : Monitor’s flicker reveals data on screen
Title Courtesy : [New Scientist : Seeing Through Walls]
Stumbled on this info at :HackInTheBox:Laptops and Flat Panels now vulnerable to Van Eck Methods