We love her, we hate her. She scares the crap out of us, and has since we were little children.
Above all, we envy her for her flying monkeys. We always wanted them for our very own.
Who would have believed that in 1939, a film character would so invade the American psyche? Margaret Hamilton, I think, defined the look of the witch for all time: Black dress, green skin, evil cackle and pointed hat screams "witch" to us to this day.
She was one badass witch. Christine over at Fascination With Fear wrote a pretty spanky post about her, so I won't make the attempt.
I do want my own flying monkeys, though.