I was thinking about glass breakers lately (like those seen on city buses) and I found out about these Bust-A-Cap end caps for flashlights that basically turn your flashlight into a glass breaking machine. Check out the demonstration video above and see how easily you can hit glass and have the whole pane shatter.

The best part? They sell these end caps for consumer-grade Maglites which is great if you keep a Maglite in the car for emergencies.