Every time I practice meditation I use the Neurosky to record my brainwaves and then you can chart how your brain is changing (if at all) over time! Pretty neato, right?
A really cool thing about the Neurosky Mindwave is software that allows you to record brainwave information during meditation sessions and chart those data over time!
The headset measures 8 brainwaves (Delta, Theta, Low Alpha, High Alpha, Low Beta, High Beta, Low Gamma & High Gamma) and also has a chip-set algo that reads these 8 wave-forms in real time and outputs them in two additional channels called "attention" (one-pointedness of mind) and "meditation" (openness of mind).
On Thursday evening, I finally managed to get the NeuroSky headset I ordered working with my computer! The headset is a BCI (brain-computer interface) that measures your brainwaves in real-time and sends a stream of data wirelessly to your computer where it can be used to interact with computer programs.
Here's a photo of my playing one of the simple games that comes installed where you try to make barrels on the screen explode by focusing your attention on them.