Store/Business Doors
In operating principle, it's identical to the chain link fence gate. The trick to implementing this with the best possible fit of the door to the building is to build the fully-functional doors first, then assemble the walls around them; the doors remain independent objects. This means, of course, that if the building is removable, the doors remain with the base, or whatever the mechanism is assembled upon.
This effect can be seen at the Laundromat/Barber Shop on the Men At Work diorama.