[fred cook]

Saw this once several years ago at Georgia Tech (2000 or 2001). The system there used a vat of liquid that would turn solid when hit with a laser. The build that I saw was of a human skull that was being created using MRI scans as the data source. The purpose was so that a surgeon could do a practice operation using an exact replica of the patient's skull. The skull being made was the exact size and shape and was hollow on the inside with the bone thickness correct. Very cool piece of equipment!