This new DS game from SEGA called Heart Scan works as a sort-of lie detector and uses the microphone to detect emotion and intention in voice patterns.
The game went on sale on the 16th in Japan, but will probably not release in the US.
Heart Scan uses "sensibility technology," which was developed by Advanced Generation Interface Japan Inc. and SGI Japan. The initial use for the tech was to monitor worker moods over the phone.
