Mind-controlled videogames are here 14 years ago
The stuff you mention about muscle/movement artifact for the NeuroSky device is not entirely accurate.
Check the April edition of the journal Clinical EEG and Neuroscience http://eeg.sagepub.com/ (out soon) it has a paper about the validity of the NeuroSky device.
Happy to talk about this more if you're interested.
sjohnsto@uow.edu.au
Dr J.