Billy Chasen built a system that uses SMS to control a door lock.
Turntable.fm co-founder, artist and software developer Billy Chasen created a way to lock and unlock his office door using a text message. No more need for keys, he simply sends an SMS to a white-listed phone number with an instruction to either ‘open’ or ‘close’ and the lock mechanism responds. Chasen used Twilio to hand the SMS sending and receiving and won a contest on their site for his project. You can view the code for the SMS-controlled door lock on GitHub and see a video demonstration below: