Learning to Purge

It seems like the stuff in my house multiplies like rabbits. I'm hoping to clear out some of the clutter and even raise a little bit of money to buy a replacement dishwasher - (I melted mine . . .long story.). I stumbled across this post on A Nation of Moms about a 15 minute purge. I don't have a lot of time during my day to totally re-organize my house, but I'm thinking I can scrape up 15 minutes. I know I definitely have my work cut out for me. I've heard of people using save, donate, trash bins as they go through their stuff. Do you have a system that works well for you? I know that with just a little bit of organization I can help eliminate some of the clutter in my home. What do you do to cut back the clutter?