I know this has probably been discussed, but it's funny to me how, until the last couple of years, most hot stuff would produce an almost immediate sweat response for me, mostly the top and back of my head, although different peppers would make me sweat in various regions of my pointy head. But, this is not happening anymore, since I've been eating serranos every day, maybe Tabasco, too. Habaneros are still a bit much, have to be careful with them. Also keep sour cream and a glass of milk, or even ice cream at hand when I tread into that territory.
But another question, beyond the sweating thing, is: Do others get the rush of natural pain killer effect that I do? Endorphins? I burn my tongue with hot stuff, and I feel pretty good for a while, it's like a shot of morphine.