I can't speak for the NeuroSky, but I reverse-engineered the protocol and crypto used for the Emotiv to create the open source Emokit ( https://github.com/daeken/Emokit ) a couple months back. While no one has really done anything with it yet, it opens up some fun stuff. The Emotiv has the benefit of more sensors, and it isn't much more expensive. I'd love to see someone do something really cool with it.