RC Deadbolt for your Door

For around $30 you can build yourself a remote control deadbolt which comes in handy for a house door, garage door or shed door. It uses an X10 automation controller mixed with some solenoids and a metal bar. When you want to keep people out, just hit the button and you are locked in and safe. All I recommend now is that you wire up the bedroom lights to flash a couple of times and for the alarm to chirp as you hit the lock button when leaving your home.

Via: Lifehacker and Instructables