A convincing twin of Darth Vader stalks the beige cubicles of a
Silicon Valley office, complete with ominous black mask, cape and
light saber. But this is no chintzy Halloween costume. It's a
prototype, years in the making, of a toy that incorporates brain wave-
reading technology.
Behind the mask is a sensor that touches the user's forehead and
reads the brain's electrical signals, then sends them to a wireless
receiver inside the saber, which lights up when the user is
concentrating.
