Another interesting and somehow improbable research project: Annotations of Prostheses (still at the University of San Diego):

The orthopedist annotated this mold of a polio patient’s right leg to represent areas from which to refrain from filing. This mold goes on with a form to a fabricator. The shape and markings on the mold, with the form, allow the fabricator to create a custom-made brace from patient-specific physical information.

The fabricator is preparing a mold to fit an orthotic brace, filing it to a shape similar to the patient’s leg. He is also providing information on where the orthosis should apply pressure for support, considering the texture of flesh at different points. The ink of the pen is well suited for deep penetration into the mold, avoiding loss of information through filing.

The reason why they are interested in this is that they work on annotations. They're point is that annotations are of communicative and cognitive importance (as aids in information movement, memory, attention, and organization). Now it would be nice to find sociological research about mold annotations practices!