Once when I was a kid I was looking for my copy of "Hound of the Baskerville's" and I looked all over for it in a box I'd seen it in on the front porch. Nothing. I went back there sometime later to search for something else and there was the book that I hadn't been able to find. Don't know what happened. Maybe the sock fairies borrowed it, didn't like the story, and brought it back.
