That plain, white, cheap vinegar you can pick up at the grocery has an unbelievable amount of uses around the home. Why? Vinegar is a natural germ-killer. The Heinz Company has produced research studies showing that white vinegar will kill 99% of the bacteria, 82% of the mold, and 80% of the germs it contacts. And, it's natural, biodegradeable, and safe for kids and pets.
How to use it? Use it straight to clean toilet bowls as well as kitchen cutting boards and countertops (let all set for 30 minutes, then rinse). Put a bottle into the washer and let a cycle run. Clean windows with a spray bottle filled with a dollop of vinegar to a bunch of water (10% vinegar, 90% water).
In gardening, vinegar is amazing. Put it out in a jar top, and the bugs run. Put a teaspoon in the vase water, cut flowers last longer.
There's lots more at about.com, 131 Uses for Vinegar.