I decided for my first tech demo to experiment with the PIR (Passive Infrared) sensor.  If an inanimate object or something cold passed by the sensor, it would not react (Outputting a 0).  However, if something warm blooded, such as a human or dog trying to steal my cupcakes, then the sensor would react (Outputting a 1).  If the input is High (1) then the buzzer will go off, alerting me of the motion.

My Setup: