If only it was a green laser pointer as well it could be a modern day swiss army knife.

That's actually a very good idea. Know the drunks out there have no excuse to drive drunk!

I'm not sure about this device specifically, but i know that those breathe strips and other BAC things that been very inaccurate. as a state attorney's office employee, i'll go ahead and warn people. not only does it suck to get in a wreck, but a DUI is VERY expensive and takes up a lot of time.

I'd feel embarrassed buying one. It is a good idea, but relies on the ability that a drunk person would think rationally enough to obey the meaning of the lights. I'm not sure how effective it would actually be in practice. The most effective solution is one that ties into your ignition, or even better a portable lockbox that only opens if you're sober. Also, blood alcohol limits vary from state to state so it would surely have to be configurable. The UV feature would surely come in handy because here in NYC I'm always worried about all the sun I get.

What if your so drunk you blow into the wrong end and the light stays green?

Yeah, cuz if you're drunk and you're alredy behind the wheel, a stupid little pen is really gonna make you change your mind... I live in the Southern US, where drunk driving is practically an Olympic sport. Most of the DDs around here would use this thing as some measure of their prowess. "Dude, that light was totally green and I made it home just fine!"