Thanks guys.
Floyd86: The facial expressions were interesting to make. I drew a series of expressions in Corel Draw and exported them as BMP's, which I used to generate transparency maps for a series of materials, each black in both ambient and diffuse, with zero specular. When applied to a flat plane, the plane becomes like a sheet of transparent film with the facial expression on it. I copied the plane as a set of individual objects, each with a different facial expression material applied to it.
In scene mode, I added all the facial expression "overlays" into the same physical space relative to the eraser, positioned over the blank face area. Each overlay's visibility was set to "off". Then, when it came to animating, I could change the expression by keyframing the visibility of each expression overlay, taking care not to overlap them or leave blank frames.
Once the scene was set up, animating was easy, so early on in the construction of this project I created a template scene, with the eraser man and all his faces in position, as well as the table top and light setup. Then, for each new scene, I just had to import this basic scene into the project again, rename it, and I had a new blank scene ready to go.