The freecycle group where I am is pretty dead. I've posted things to get rid of & "wanted" posts and my post never even shows up. I don't think we have a good admin for our area.
I'm fairly shameless, I'll stop & load it up if it's worthwhile.
I've gotten tons of lumber, washtubs, milk crates, plant containers, mulch (I always ask if they spray their yard, and won't take it if they do) a wooden herb spinner with all the glass jars & lids, tables, chairs, a futon frame in perfect condition. My mom & dad have found TVs, brand new comforter set, bikes, toys.
Thankfully, people tend to set things out away from their regular trash, so no one has to "pick" through to get the good stuff. Plus, the "rich" neighborhood folks tend to set stuff out early in the week, so you have time to get it before the trash truck comes. Also, rural folk tend to dump things off the sides of our gravel roads (bad!) if they don't have a bulk pickup day (I roam through 4 counties, so there are different guidelines for each)
Those are great to look through. Cinderblocks, I mean really, who throws those away? I found 6 of those in perfect condition, never even been mortared in place, just tossed out among the tree trimmings & defunct washing machines.