My favorite use is to clean the carpet in my car. My kids have found some really creative ways to stain it, and the peroxide has removed it all. (well, except for the red icee..)I have found that using a fresh bottle works much better.
A lot of people use it for everything since it is so" green". I like it because it's cheap! In a funny coincidence, my sister did a post about using rubbing alcohol to clean with here.