Hi Doc, I've been referred by...my car!

It can measure heart rate, skin conductance and oxygen saturation in the blood, and the “vision is to get the vehicle to detect when the driver is no longer feeling well”, researchers said in a media statement.

“When a stress situation is detected by means of skin conductance values, phone calls can be blocked, for instance, or the volume of the radio turned down automatically,” said Professor Tim Lueth, from Technische Universitaet Muenchen. 

“With more serious problems the system could turn on the hazard warning lights, reduce the speed or even induce automated emergency braking.”