Andrew writes –

Our favorite new iPhone hack, the duiPhone, will let you know for sure whether you should hand the car keys to a friend after a long night in the bar… Once you blow into the mouthpiece, the application will determine your blood alcohol level – either telling you you’re good to go, or that you should consider calling a cab. We built this from a store-bought-and-hacked breathalyzer attached to a 3G iPhone – our first experiment with Tellart’s newest Sketchtool: NADA Mobile. Yes, this video was taken at our office. Yes, those are real 40s on the table.