In May, in Japan, the Crown Hybrid will be introduced with a Pre-crash Safety System. A camera at the front of the car will monitor the drivers upper and lower eyelids to determine if the eyes are properly open. If they are not, there is no indication what happens inside the car. I'm guessing a tug-boat horn.
Implications - Either way, car sense alertness is a really cool concept that would likely save many accidents and even lives. Leave it up to Toyota to be on the cutting edge of safety!