I am going to go against the grain and say places like Salvation Army thrift stores are a great place to donate previously loved items. When I last moved 12 years ago, there was lots of good stuff that didn't fit in the new house but was still totally usable. Instead of having to pay someone to haul it away as junk, they were all donated to Sally Anne for resale.
Quite a few years ago I found a fully functioning R.O.B. for $5. Honestly, the only reason I bought it was I thought it did more than what I thought it did or mistaken it for something else that I used in a store as a child.
I still have it and on ebay, it's about $100-200. So I guess it was worth it?
Mine was a RiteTemp oil radiator, works perfectly and keeps my apartment toasty warm in the winter. I don't recall how much it ran me, but it was a nice find back when I bought it a year or so ago.
I was in one today and found a shirt to compleat my "Don Cherry" look for coaching a hockey team at the Canada senior games next week in New Brunswick.
I got my Android tablet and also my ipod touch from the pawn shops, still working fine after about 4-5 years.
A semi-rare (or at least hard to get) expansion for the original Starcraft called Insurrection. Wish the other one would have been there too, but I was so happy to have found that. That was quite some time ago. Something more modern was a Dell XPS mouse pad. I was going through the cloth ones fairly regularly but this hard surface pad has lasted at least 100x longer than any old pad.