@Fiddle_Playing_Creole_Bastard Awesome choice. I grew up watching that too, and to this day, Pennywise still amazes and delights. :)
However, my choice is Michael Myers. He’s my hero, and completely traumatized me when I was 11. There’s not much to him at first, and maybe it’s just in my head, but his lack of anything besides the drive to kill is what amazes me. It makes the clichéd emotional resurfacing moments all the more believable, too.
As for television shows, I’ll always love Callisto from Xena Warrior Princess. She’s pretty, selfish, kicks ass and is a total bitch, plus she just won’t die. She even made Xena feel bad.
But again she’s one of those villains who was shaped as such by events they couldn’t do dick about, and is now fueled by anger and sorrow. I like all those tough on the outside mushy on the inside emo characters.