Habitat for humanity. But they need to be in fantastic shape.
I also use habitat for humanity. Often they will come and pick the items up. If your are going to drop them off, call to make sure they will take them. Next best is craigslist and freecycle.
As someone else mentioned, Habitat ReStores take a variety of items, and every ReStore has a flavor of its own. Some of them are quite picky about what they take in. Others, such as the one in Grass Valley, California, revels in the older and more eclectic. Some have a thriving vintage or upcycle business while others deal in new or like-new only. Check with the Habitat ReStore(s) in your area to get a better idea.
Salvation Army is who I use of my church