Some more context is available in this Reddit thread:

http://www.reddit.com/r/discworld/comments/2ysv26/sir_terry_...

Rather beautifully appropriate. I'd be delighted to see this adopted, and would myself, if I ran my own webserver these days.

Yes, let's waste 40 bytes on EVERY SINGLE HTTP REQUEST. That's a fitting tribute. What's with the pointless GNU shoe horned in as well?

Valid question, and not easily duckduckgoable. I found this explanation on tumblr, by blackboardmonitor. I wish I knew how to link to the damn thing, but I can't figure out the tumblr interface.

    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.”

    When a clacks operator died while working, or was killed, their
    name was passed in the overhead with “GNU” in front of it, as a
    way of commemorating them, of not letting them die, because, “a
    man is not dead while his name is still spoken”. It’s a way of
    keeping them alive, you see.

    Terry Pratchett, may he rest in peace, wrote the clacks as a
    fantasy equivalent of social media, of emails, in particular, but
    general interweb communication as a whole. Therefore, people are
    posting “GNU TERRY PRATCHETT” because it’s the equivalent in our
    world of commemorating him on the clacks; we’re keeping him alive,
    in a way, in a way which I think he would have liked.

    Because no one is really dead until the ripples they caused die
    away. So, now & until I myself die: GNU Terry Pratchett.

I don't see any real connection. The HTTP header doesn't make the requested web page be sent over and over.

A better way would have been to establish a series of SMTP servers ("towers") that forward the mail in a circle endlessly.

Let people subscribe to that kind of mailing list, getting one mail per day. And let the SMTP chain exist as long as there is one subscriber left.

I'm considering a cookie instead of an X- header, to at least mimic the "U = turn it around" aspect by the browser sending it back next time...

GNU stands for something specific in one of his books this tribute is coming from.

It turns out stuff like that is already done.

I just found out, by viewing that thread, that reddit responds to GET requests with the X-Moose:majestic header.

Because that's the way it was in the books. The GNU code needed to be there to make sure the name is spoken forever.

If you're caching your content properly and sending 304's when appropriate, this header won't get sent with every HTTP request. And if you're not using 304's properly, you're wasting a lot more than those 40 bytes.

http://www.orangutan.org.uk/ and http://orangutan.org/ oblig. plug for Orangutan Foundation (UK) and Orangutan Foundation International (US), who try to protect them and their habitat.

was the ad at the bottom of the page really necessary...?

Didn't even notice that, I've an an blocker on - the id of the element is "shamelessmoneygrab". Hmm.

Yes, as everybody knows, web hosting is free.