Capturing Emotions and Mental Conditions

Last weekend, I built an application to track emotional and mental state using an Emotiv headset to overlay realtime data onto the image of the person.  When a smile is detected, the application takes a screenshot of the page being viewed and overlays it with the image of the person smiling.  

With more work, emotional and mental state could be shared in a more intuitive/creative way.  Imagine a skype call were you see the persons level of excitement/boredem via some graphical overlays.  Additionally, it could be used to track mental state and capture meaningful moments when working.