Pennywise the clown is responsible for many a childhood nightmare and for good reason. The entity from Stephen King's 'It' became all the more real and terrifying in the made-for-TV movie adaptation, stalking childhood best friends and making their lives a living hell. Tim Curry's performance as Pennywise is enough to make people who aren't scared of clowns pee their pants with those crazy eyes and big, sharp teeth. We know it should sound silly, but "Beep beep, Ritchie, we all float down here" still gives us the heebie-jeebies.