The core of the device is simply a two by two by two cubic tile consisting of two redstone, two buddy blocks, two solid blocks, and two of any other block.
Note that so long as the redstone is placed last, the trigger will not activate while under construction, which allows it to be used as a detonator for TNT.
From this point forwards we get into move and countermove but as my current toolset of defenses is composed entirely of "Add more tiles!" I'd like to open it up to everyone else to see how it can be broken and unbroken.
Regardless of that however, I hope you all look forwards to the possibility's afforded by this device as much as I do. Enjoy.