Polish researchers have developed a laser that can be fired at cars to find out if their drivers are drunk. The device, detailed in a study published by scientists at Warsaw's Military University of Technology, can detect alcohol vapor inside moving vehicles by using special curved mirrors and beams of light.

There are some caveats: results can be altered by a range of factors including other drunk passengers in the same car, open windows, or air conditioning. The device won't be able to detect every inebriated driver — as Popular Science points out, the US National Transportation Safety Board classifies humans as "drunk" with 0.05 percent blood alcohol level — but the researchers say that their creation will both decrease the number of cars police check, and increase efficacy of stopping drunken drivers.