Kyle VanHemert, writing for Wired:
A Kinect camera mounted above the sandbox tracks the physical activity below. As visitors young and old go about their terraforming, a projector throws a dynamic topographic map on top of it all, updating contour lines and elevation colors in real time. Then, the fun part: a virtual rainstorm, also supplied by the projector, sends a torrent of blue water cascading down the peaks, showing runoff and watershed on the landscape created moments before.