The ability to locate things is fundamental to life. Throughout history man has developed means to categorize, map, track, and control items of value. In today's world, the necessity to track, locate and control things is interwoven into the activities and products we use personally and professionally every day. Everything from tracking packages during shipping, counting inventories, locating emergency personnel, and capturing actor body motions for animation production are all examples of how sophisticated the "locating of things" has become. However, simply knowing the locations of these items of value is not enough; we have devised means of communicating to and from unknown locations and through these communications we control these items of value remotely. Our very quality of life depends upon these abilities.