For a nanonovel, you have to stop being generous with regard to concessions to formal aspects. “The End” is out.
I played around with the idea, tested some drafts with plots from literature and movies, and had to make my first concession: Adding [ — The End.] or [ “The End”] (without the brackets) to my nanonovels is out. That’s either 11 or 10 characters (not 12, what exactly was I counting in my last post?!?) out of 140, that’s around 8 %. That’s quite a lot. 140 characters is Mission Improbable already, no need to veer toward Mission Impossible.
And I’m still not sure whether I can pull this off.