Um. I take books out of skips, I pick up books in giveaway book shelves (like book crossing) ... but that all seems so common. I got a copy of The End of Mr Y this way, a total find to get an amazing book while on holiday, buried in bunches of cheesy romances and uninteresting suspense novels.
I have a copy of 1984 that I bought twice. I got it as a gift for a friend, inscribed it, and gave it to him. A few years later I went back into the same book store and there it was, with my inscription in it. He'd sold it back. I felt sorry for it and bought it again.
Is that actually interesting?