Wow! That is an awesome idea!
In 2012 alone Singapore had to face over 2100 cases of drunk driving, some with disastrous endings. The club Zouk engaged an agency to keep their guests from driving when they definitely should not drive anything anymore by themselves and they managed to come up with a fun way to do so: the Pee Analyser.
Former parking cards were replaced with RFID cards. As soon as the drivers used the toilet the cards got activated through a urinal testing device that measures the alcohol level in the urine. If they were hammered, they got the strong recommendation to take a taxi or could even use the clubs’ drive home service.