So apparently there is a secret way to remove questions from the Hot Network Questions.
Look at this question. The original version made it to #25 on the HNQs. After Emrakul's edit (adding some invisible characters to the title), it disappeared from the HNQs altogether. I thought this was a little odd at the time (and also thought Emrakul's edit was very odd!), but ascribed it to coincidence and the fact that the HNQs change rapidly. Later I saw Emrakul's edit description "prevent HNQ entry", and realised that - without consulting me, by the way - he'd manually removed my question from the HNQs.
Adding the code
$\;$
to the end of a question's title automatically removes it from the HNQs.
I thought this was something the community should know about. And to make this a question rather than just an informative post (this might be meta, but it still seems to be mainly Q&A!), let me ask the following:
why have we never heard about this before?
There has been at least one previous meta post about HNQs and the issue of removing questions from it, which according to the accepted answer is impossible. Googling stack exchange remove questions from HNQs or stack exchange remove questions from hot network questions yields no relevant results. Is this something secret that non-moderators aren't supposed to know about? If not, why hasn't there been a blog post about it or any discussion on any meta that I can find?