We’re a month into the Guardian’s Bookswap campaign and thousands of free books have been left in public places all over the UK. It follows in the footsteps of a growing number of book swapping sites such as Book Crossing, Book Mooch and Travelling Suitcase Library in which people stick a label in a book, explain why they liked it and then leave it for other people to find. So next time you’re at Seville Airport feel free to take home the excellent “You’re Next” by Gregg Hurwitz. It should be on a table in the departure lounge, next to the shop that sells Parma ham. That’s where I left it anyway.