Unlike those old shoe-shop machines, there's no harmful radiation involved. In fact, the system is pretty much just a projector that overlays an image of the car's bones on top of the metal, making the body only seem transparent. The system can be set up to work with different models, so if a customer wants to see the unseen differences between a VUE and the new Outlook, the dealer can just wheel one or the other into the beam. Animation is also possible, and could be used to, for example, show how the Vue Green Line's hybrid engine works.
The technology comes from a company called Obscura Digital, which has worked with numerous other automotive companies. A video of their work with Saturn is available on their site, but is, unfortunately, not able to be embedded here. You'll have to click the link above to view it.
[Souce: Advertising Age]