Abstract
We describe ProDesk, an ubiquitous, projection-based touch surface system that extends the screen space of today's desktop computer workplaces to the whole surface of an ordinary office desk, along with highly accurate multi-touch interaction. The objective of this system is to offer users more flexibility on tasks in which lots of complex information have to be handled. We propose a novel user interface concept that extends normal WIMP functionality and a software architecture that implements this UI concept. We present evaluation results of the system in technical benchmarks and a user study.