Post Office Bay, Floreana, Galapagos. This is where the whalers used to leave letters to be collected by passing ships, as early as the 18h century. Now it's used by tourists to save on postage - they leave postcards in the post barrel and other toursits come and sift through the pile to find things going to their home countries and take them with them. Apparently this is more efficient than the Ecuadorian postal service.