Whenever I am abroad I fail to send postcards, mainly because I often fail to find a mailbox. Since sending postcards from home doesn't feel good, it would really help if there is a file with lat/lon coordinates of mailboxes in the EU. I could load the file into my personal GPS and it will direct me to the closest mailbox.
Such files exists for ATM, but I never have found one for mailboxes. Does it exist?