How to Shatter a Car's Tempered-Glass Window Using a Busted Spark Plug

The clip below comes from a National Geographic program called Hacking the System: Hack Your Car that airs on February 27 at 9:00 PM EST. It shows just what it takes to get through a car window and gives a handy hint on how to breach through tempered glass in a crisis. Scroll down to check out the video, but be sure to only try it on your own car.