Item Theft Detector - Detect Items Taken or Placed in a Chest - Minecraft
Channel: Chartreuse Kitsune
Date: 2013-01-13

This simple circuit using comparators is a way of saving a state of a chest and checking if items have been taken out of it, or placed into it. While it might not be the best protection on servers, for custom maps where you might want to trap a chest that you don't want to blow up until they remove items from it, or add some more, it fits in perfectly. One other benefit of it is that if you break the comparator right after the chest or a good percentage of the other components it will set off as well.

This could be hooked up to some TNT elsewhere or maybe drop the floor out from under the person, or a wide variety of other traps or alerts.