A 3D digital audio signal processing system, a 3D tracking system, adapters for wireless network technologies capable of position location (radio, infrared), six notepad computers, one workstation, and bus expansion boxes to connect peripherals to the requested workstation and existing computers shall be obtained in this project. This equipment will be dedicated to support research in the Computer Graphics and User Interfaces Laboratory and the Mobile Computing Laboratory, both within the Department of Computer Science at Columbia University. The equipment will be used for several research projects, including in particular: development of "hybrid user interfaces'' that merge 2D and 3D displays and interaction devices; design of "augmented realities'' in which the surrounding physical world is annotated with knowledge-based 3D graphics; development of virtual worlds for multivariate data visualization; invention of methods for ``bandwidth aggregation'' achieved by combining distinct wireless network channels into a single high-speed channel; and development of means by which application programs can sense their location and ``localize,'' customizing themselves to their physical surroundings.