Well a company called InteraXon would like it to be a headband which would allow us to use our thoughts to control our computers. Currently the company is trying to raise $150,000 on indiegogo for a sci-fi looking product called Muse. There is not much information on exactly what you will be able to do with Muse, but it seems at this point they are promoting more the idea of using it as a self help tool (say to improve concentration, lower stress, etc.) as opposed to controlling gadgets. I'm sure this is due to current limitations of such technology but I think it is probably only a matter of time before such devices will be fully developed and in widespread use.