If you happen to be walking in your local park tomorrow and you find a book with a label inside (1) ... Read and Release me," don't just treat it as a (2) ... . You've probably (3) ... across an example of bookcrossing, a book-sharing movement (4) ... in 2001 by American software developer Ron Hornbaker, whose aim is to "make the (5) ... world a library'. Bookcrossers "release' books either by (6) ... them on to friends, or by leaving them in public places for others to (7) ... up, or 'catch', and then read, before they in (8) ... release them back "into the wild". Over half a million people worldwide take (9) ... in bookcrossing, "releasing books in cafés, airports, bus stations, telephone boxes. Often a book is left in a place which is associated with its (10) ... or content: Agatha Christie's Murder on the Orient Express on a train, for example, or an archeology book in a museum.