Goodwill is a great place to take all the useable stuff piling up around your house. I like this one because the people working the drop off are always really quick and helpful.
They have a huge variety of stuff you never knew you needed. After you get rid of a carload, you can use the discount coupon on your receipt to pick up the patio furniture someone else didn't need or that Bob Marley T-shirt you didn't expect to find.