Last year while Christmas shopping my best friend and I stumbled across a used books store. I found lots of things I wanted, and she found a couple of vintage black and white film noir movies. I never knew she liked vintage movies!
Anyhow, the upshot was that later in the week, I took in a large box of books that I no longer read. They were collecting dust on my bookshelves. I traded all of them for the two vintage movies that she liked and one of the books that I liked.
Imagine my surprise when she and I exchanged gifts, and I found three of the books I had wanted from the exact bookstore. Great minds think alike! We are doing it again this year, only we're both taking our books in at the same time, and shopping for one another while we are there.