Over the centuries vinegar has been produced from many stocks, including molasses, dates, sorghum, fruits, coconut, honey, beer, maple syrup, potatoes, beets, grains, and more. But the principle is the same: You get acetic acid (a.k.a. vinegar) after first fermenting natural sugars to alcohol, and then fermenting again.

As Michael de Jong, The Daily Green's Zen Cleaner and author of the Clean series of books, points out, vinegar has been pressed into service for many uses over the centuries. It has been prized as a foodstuff, condiment, preservative, and natural remedy.

What's so great about vinegar? Besides being effective, vinegar is cheap and widely available. It is nontoxic and lasts for a very long time without losing strength. It does not pollute land, air, or water, and it doesn't combust. It's much safer to have under your sink than bleach, ammonia, or other toxic cleaning products.