Several companies have developed bio-sensor and signal processing hardware and accompanying software API's that allows a user to control computer systems via their thoughts and intentions. The hardware is part of a biofeedback system that reads brain waves via electroencephalography (EEG). The hardware itself is not new. EEG has been used in biofeedback systems for psychiatric use for many years. However, some new companies are looking to expand the range of computer programs that can be controlled via biofeedback. As an added bonus, these companies make the hardware look cool. NeuroSky, Emotiv Systems, and S.M.A.R.T. Brain Games are just three of the companies that are working to make this bio-feedback hardware cheaper and more useful for the general public.