The tool on this website allows you to export 3D models from Google Sketchup and view them in a live video feed from your webcame. The 3D model is merged with the live video feed and placed on top of a marker printed on a piece of paper.
Imagine in future if something like this could be used as a presentation tool for Radiology. If a patient had a marker placed on them and they could then turn around and view live realtime video overlays of CT, MR or 4D Ultrasounds. I think it would really be a fantastic presentation medium to allow patients to see "inside themselves". The technology will probably not add any diagnostic value, but I am sure it would be great for patients!