A lot of us have old stuff lying around the house. Some of us can't throw things out because we think they are still perfectly useful even if we're not using them. Some things can sold at garage sales, classified ads or Craigslist. However, some things, despite the value we think they have, are not worth much.
One of the number one things that people tend to hang on to but end up being almost worthless are books. I personally believe books are the most valuable but that's me. If you have old books and can't throw them out post them on BookMooch which is a book exchange program. You can post books you want and books you have and their is a point system where you earn points for books you post and books you give away. You then redeem points for the ones you want. I've linked to the about page for more details. There are multiple languages as well. You have to pay to mail the book to the moocher but you can get books for free so I figure you should break even.
Another way to get rid of stuff is Freecycle. It is basically a free classified where you give stuff away to people who are willing to come and get it. You can also post requests for items. The system is based on towns so you can find things in your local area and local people can come and get your stuff.
Two great ways to get rid of things we can't bear to toss away.