Zhao Wencai and Li Zhoumu, two graduate students at the China University of Geosciences, have concocted a prototype device which checks for two important bits of information before allowing a car to start.
First, it scans your fingerprint to make sure you're on the authorized driver database; second, it scrutinizes the sweat on your digit to determine just how sober or inebriated you are. It does all this before the car will even start.
Although there is technology that, if not already out, is coming soon that does something similar, I don't believe that this invention will fly very well. That is, in the states at least. We'll see though. I have been wrong before.