If you're out for a drink and planning to drive, you want to know that you're keeping yourself, your passengers, and other drivers on the road safe. Breathalyzers used to be a device used only by police departments, but now you can get your own for less than you might think. Breathalyzers are easy to use; you just need to push a button and breath into the device. The device will show a reading on the LED display which measures your blood alcohol content. If it's over the limit in your state, it's time to hand the keys to someone else.