Mail Puzzles by Harriet Russell

For her degree from the Glasgow School of Art, Harriet Russell decided to do a little postal experiment to find out exactly how far would the men and women at Royal Mail were willing to go to deliver mail:

To put them to the test she concealed the addresses of 130 letters to herself in a series of increasingly complex puzzles and ciphers. Among the disguises she employed were dot-to-dot drawings, anagrams and cartoons. The answer, it seems, was very far indeed. Amazingly, only 10 failed to complete their journey back to her.

The story is fascinating (complete with reference to how the private secretary to Queen Victoria also did this sort of thing): Link – via Laughing Squid