A good source for heavy free things is Craig’s list – an excellent classified ad site.
You will want to get to your local site so choose your state from the state list.
Now under the For Sale listings – select free.
Now type in your city in the search for box – and you will find a listing of free stuff in your own kneck of the woods! Diving boards, TVs, pianos, sofas, firewood, mattresses, and furniture all popped up in my search! All useful stuff for comfortable living in a space ship!