Another great use of shields for creative electronics especially for offices and shared flats is the toilet hack. 

But what the heck is a toilet hack? A most useful thing: who doesn’t know the situation when you have to use the toilet and then - occupied. Again. But those times are over now. Your mobile phone becomes even more useful and indispensable the toilet hack app makes you see always right from your seat if the toilet is occupied or not. If your workmate takes too long, just use the app and the toilet hack knocks the door for you.

 

What is needed to make it to reality? Use the Spark Core Microcontroller and the according shield made by us. Further ingredients are: some cables, a tilt sensor, a little solenoid motor and something to hold the motor.

Attach the tilt sensor to the shield where it says lock and the motor where it says knock. Then just get creative and build something to hold the motor in place to knock at the door; we used a styrofoam block for it, made a hole for the motor and just taped it to the door.