Mind controlled skateboard project for university, The higher the concentration level, the faster the skateboard goes!
(Sorry about the shot of the fish watching, I was just putting the headset on at that point! Also the video is a bit boring after a while!)
Used an Arduino to design the circuit, then built it on some strip board. There is a notification light on the top of the skateboard to let you know when the headset is connected to the board, also an LED array to show the attention levels. Full attention is when the last 3 red bars are illuminated. (Cannot give the code out sorry as this is my university project at the moment.)