How cool...

[penfold]

Check out this video from TED...
Tan Le: A headset that reads your brainwaves | Video on TED.com

If you get bored at the beginning just skip to about 4.30 in.

[SYNACK]

Expencive though at the moment and you need to fully wet each of the sensor pads with salty water each time you use it so its got to feel a bit weird. They are working on the dry sensor pads but they were still some way off the last time I checked. Does look really dool though and the more the technology develops the more useful and impressive it will be.