Breathalyzer

The ONUSblue alcohol detection patch tells you when you've reached the legal threshold and has the potential to save millions of lives. The company's product roadmap is even more interesting with the detection of marijuana, methamphetime and a range of illegal recreational substances to follow.

The prototype AlcoStop system measures drivers' blood alcohol levels by analyzing their sweat via built-in sensors. If those levels indicate that they're too drunk to drive, the system won't allow the car's engine to start.

Indeigogo project Breathometer is key chain sized breathalyzer that works with your smartphone

France is attempting a bold solution to the problems of drink driving - from July of this year, it will become law in France to have a working breathalyzer in every car on the road.