The Hinge
This hinge contraption may be your best invention yet! It resembles an ordinary iron block when closed, but a narrow bolt of dark iron allows two heavy slabs to rotate up to a half-turn.
When placed, one half of the hinge will be securely anchored to the world; blocks placed on the other half can rotate freely when pushed or pulled with an empty hand.
Giving a good smack to the hinge block itself will make it slam shut.
A redstone signal will lock the hinge in place.
Comparators will measure how far open a hinge is.
The heftiness of the hinge allows the construction of much grander doors than those rinky-dink wooden ones 
.
Only the first block you place needs to be attached to the free end of the hinge; other blocks may be placed and removed however you desire, but no further than 8 blocks away from the hinge.
Hinged contraptions can be pulled open or closed using winches.
Sockets and servos function on hinge like you would expect, for the most part.
Workbench.name
Hinge
