I can remove them from the wiki in /r/GNUTerryPratchett but you'll have to speak to the original author to get them removed from his comment
https://www.reddit.com/r/discworld/comments/2yt9j6/gnu_terry_pratchett/cpjwu19/
https://www.reddit.com/r/discworld/comments/2yt9j6/gnu_terry_pratchett/cpjw4ie/
thanks, added :)
https://www.reddit.com/r/discworld/comments/2yt9j6/gnu_terry_pratchett/cpgpdf7/
For exim a simple addition to the smtp-transport will add the header to all outgoing mails. Just add > headers_add = X-Clacks-Overhead: "GNU Terry Pratchett" to the remote_smtp transpo...
https://www.reddit.com/r/discworld/comments/2yt9j6/gnu_terry_pratchett/cpgp6fh/