Maybe it’s because I have a strong personality type (can fry a goober from 10 yards with a simple look), but I find that smiling a wan, Mona Lisa type smile and responding with cool, short answers tends to give them the impression that I’m just not that interested in pursuing further conversation - sometimes using that “Mother-to-slow-witted-child” attitude has to be added.
I, too, am a walking weirdo magnet - have been all my life - so that might be the reason I’m more tolerant of those poor fools who feel compelled to befriend me. I’ve had lots of practice at diverting their attentions without being cruel, rude or unreasonable. Hey, sometimes you even have to be honest with them to get a little peace, but you don’t have to be mean when doing it. We’re all walking this little space of land and using the same air; trying to get through it as painlessly as possible is all most people want - even the weirdo’s. And, aren’t we all somebody’s weirdo?