This is very, very cool - one can only imagine Da Vinci's delight had he known this thing would actually be built and played all this time later!

Sadly, the demo video is incredibly useless. Not only is it an obnoxiously cut-together collage of song fragments, it also never shows how the organ actually works. They do show off the room it's standing in, the pianist, and the audience in detail, but not the instrument nor do they do an acceptable job at providing a good listening experience. One can only assume this is by design, since the article is pretty vague on the inner workings of the organ as well.

Still, the project itself is very neat. I'm looking forward to hearing more from the viola organista.