There's a "non-invasive" brain-computer interface on the market. It's a little less ambitious; targeted towards people who practice meditation. https://en.wikipedia.org/wiki/Muse_(headband)
It's a very bare-bones EEG system: the Muse has 4 channels and a few references; EMOTIV has either 5 or 14. The slick part is that they use "dry" electrodes, which do not need to be filled with a conductive gel before use. The signal from wet electrodes is still a bit better (less noise, etc), but the gel is fairly gross to have in your hair.