Letterboxers stamp their discoveries in a personal journal, then use their own rubber stamp, called a signature stamp, by stamping it into the logbook found with the letterbox, perhaps writing a note about the weather or their adventures in finding the letterbox.
Letterboxing is a hobby... but it is more than that. It is a chance to get out and experience someplace you have not been before. It is an exercise in following directions and your instincts. It is an opportunity to meet, make and keep friends. And it is an outlet for your own creative energies and to enjoy the efforts of others.
Letterboxing is a hobby, yes, but what a sweet addiction it is.