I've made one of these as well using the 'original' setup. We used rags and blocks as I figured a sandbox in the living room matched with two small kids would h

I've made one of these as well using the 'original' setup. We used rags and blocks as I figured a sandbox in the living room matched with two small kids would have been a relative nightmare. Holding your hand over spots, this making it rain, and having the water "pool" and run as it would is absolutely beyond fun. Move the mountains, and downward it continues to flow. With a budget projector ($82!), A Kinect (I forget version), and an old graphics card it worked pretty flawless after setup -- probably the hardest part was aligning the sensor with the projector and getting it all actually calibrated -- the next one we build I'll def try this version and note the differences. Calibration with the other method used a cdrom as it's target that you placed around, a bit fiddly. Super super cool.