Terry Pratchett sadly passed away in March 2015. The phrase “GNU Terry Pratchett” has become a term used by fans to mourn and memorialise him. As well as being written by fans in messages, it has also been embedded in the infrastructure of the internet as a tribute, inspired by its origins in Going Postal.

In Terry Pratchett’s Going Postal, the operators of the clacks tower use “GNU” as a code to mean the message should be passed onto every tower. An article on wiki-Lspace says that “The G in the code means to send it on the U at the end means to turn the message around at the end of the line and the N means not logged.”