Sometimes it's hard to tell when you've had too much booze, and that's where the personal breathalyzer comes in. Thankfully UK retailer Boys Stuff knows that most people interested in such products probably spend all of their money on hooch and can't afford one of the nicer models, so they're offering a "budget-conscious" alternative with excellent portability but questionable accuracy ("The place and method of operation may affect the test's result by up to 5%," claim the Boys). The Breath Test Pen indicates your sobriety level by flashing the normally-green LED red after an alcohol-filled puff, letting you know that it's time to "stop" and call a cab, and is presumably set at the .08 blood-alcohol level threshold common to both the US and the UK. If you're still not convinced that this $35 device is for you, they'll throw in a UV sunburn tester at no extra charge(no joke, it really does that).