When I was a kid, my friend David tried to make a homemade firecracker out of gunpowder and a folded-up sheet of notebook paper (with a paper drinking straw cover for the "fuse"). When he lit it, the result was like a Tom and Jerry cartoon come to life. Huge flash, tons of smoke, it burned his eyelashes/eyebrows off, and it left little black dots all over his forehead and cheeks. That was the best fireworks show I ever saw.