I'm an old timer around here. Used to be very active in bookrings and trades, but these days I mostly focus on Random Acts of Bookcrossing Kindness. I almost always check bookcrossing wishlists and
rabck.com when I finish books, and pass them on accordingly. I prefer surprise RABCKs, so rabck.com is my go-to site :)
Want to make sure your BookCrossing books go to someone who REALLY wants them? Check out paperbackswap.com!
I found this link on another bookcrosser's bookshelf and thought it was worth passing along: www.modestneeds.org/