This nifty project was created by Randy at F.A.T. He says, “The breathalyzer microphone is a system for the inconspicuous collection of blood-alcohol content level data sets. In other words, you can measure a person’s sobriety with a device, that for all intents and purposes, looks no different than a standard microphone.”

He kindly put the how-to up on Instructables, in case you’re inspired to make one of these for use on your drinking buddies. In essence, you rip a cheap karaoke mic apart, add some wires to the XLR and the switch, make a tricky bracket, attach it to an alcohol sensor you previously ordered from Thailand, and voila. To make it portable, you can use a tape deck or something else to hide a datalogger and arduino.

Then you just have someone talk or sing into the microphone, and use a computer to get the SD card readings to get the info. Now you know fo’ sho’, that mofo is DRUNK. And you have computer data to prove it to him.

[via Make:]