With winter on the way(for those of us above 0^o lat), here's a neat trick: slowly take a file & again, very slowly file some flint until you get a bit of flint dust. This works best over an open flame but something very hot like a wood-burning stove or other hot metal surface will do. Sprinkle a small amount of the flint dust into your palm-just a little bit goes a long way, and also if anybody looks in your hand, they see nothing, that's how little bit. When near a flame or hot surface, make a fist, digging your fingertips into your palm and "throw" at the fire flicking your dusty fingertips toward the heat while doing so. Makes a bunch of sparks, people freak, look in your hand, see nothing and you do it again and again, they freak more, you smile.

Slowly turning the flint wheel on a lighter several times, and thumping it over your outstretched palm will get you some dust also.

IMPORTANT: once you have a substantial amount of the dust, it becomes even more crucial to file/turn wheel slowly, because if you strike sparks and they land in your pile of dust, it's all gonna go up like Kobe Bryant with Icy-Hot in his jock.

You absolutely do not want that going off in your hand. Pun intended.