I recently snagged a "Mind Flex" board game containing a headset with a Neurosky EEG chip. My intent is to add wifi-enabled processing into the headset via an AVR and ESP8266, or if I'm feeling a bit bolder, just the ESP8266.

Further iterations will involve seeing what can be done to minimize the size, weight, and power consumption of the entire set-up to hopefully wind up with something a bit more practical.

Finally, in some spare time I'll also see if I can't track down and/or reverse-engineer some details on the particular EEG chip inside the headset, to see if the functionality implemented in the headset can be expanded or extended.