Some people claim that moonshine can be tested for purity by putting a little in a spoon and then setting it on fire. It should burn with a blue flame (ethanol). If it burns yellow (methanol), don't drink it. Methanol (also called wood alcohol) is a poison. I don't know if this test is foolproof, so DRINK AT YOUR OWN RISK.
Moonshine can be tested for strength (referred to as "the bead") by shaking it to form bubbles on the surface. Large bubbles with a short duration indicate higher proof.
The purity of moonshine is practically limited to 190 proof due to its becoming an azeotrope at 95.6% alcohol by volume (191.2 proof). An azeotrope is a mixture of two or more liquids in such a ratio that its composition cannot be changed by simple distillation because, when an azeotrope is boiled, the resulting vapor has the same ratio of constituents as the original mixture.
Producing moonshine in the United States (even for your own personal consumption) is a federal crime. Periodic attempts to legalize spirit production for personal use have all failed to pass. The most recent attempt was in a bill introduced by U.S. Representative Bart Stupak of Michigan in 2001.
Liquor is one of the most heavily taxed consumer goods in the United States. 32 percent of the purchase price of a bottle of liquor goes to state and federal taxes (three times the tax on wine, and twice that on beer).
Synonyms for Moonshine include Mountain Dew, White Lighting, Corn Liquor, Bootleg, Busthead, Popskull, Rotgut, Bathtub Gin, Panther's Breath, or just simply Shine.