What if, instead of a touch screen, you could reach out and touch (and manipulate) an image on any surface? Seems like a cheapskate alternative to buying a touch-screen white board to me.
Japanese company Funai Electric is setting up to do just that. They’ve created an alternative to the standard touch screen, using a projector that is capable of creating the functionality of said screen on any surface. The projector uses a system of laser light and sensors to tell when an object (say a finger) has been placed over the image, allowing a user to manipulate the image using gestures. The projected image is decidedly low resolution, so it may not be a complete replacement for the Microsoft Surface technology, but it could be a budget alternative.
The projector is currently just a prototype, but the company developing it has stated that they hope to have a commercial version available as soon as early 2010.