Here's one last content addition, although not created by me. This is a clip from the 1931 film Svengali starring John Barrymore. The camera work and the exterior with all the layering effects in the first half is basically what all this 2.75D hooey boils down to. It looks like a series of 2D layers animated to create the illusion of a 3D world. In actuality this looks like a combination of matte paintings for the extreme background and miniatures for everything else:
