1. Pennywise - IT
Tim Curry has made a career out of freaking us out. But no other character on this list can claim that they've actually given people clown complexes. Pennywise, the evil sewer monster that feeds on children's fear, is possibly the scariest monster in the history of things that go bump in the night. Either in Stephen King's book or in the film, he never fails to make us all turn into a sobbing little child in a yellow rain slicker.
2. The Thing - The Thing
The best thing about John Carpenter's "thing" was that it could be anything or anyone, but where this monster excelled in terrifying us all was the fact that you got to watch the beast mutate into a human/spider/dog beast from hell.
3. Samara Morgan - The Ring
After watching The Ring in the theater I came home and put a towel over my TV so nothing could crawl out of it. Many who watched the dark-haired demon child climb out of the television had a similar experience when they got home. This is the mark of a truly evil character. You could argue that the original film, Ringu is just as good if not better, but I feel the translation was equally scary, so they can share the spot.
4. T-1000 - Terminator 2: Judgment Day
Have you seen this boy? No, but I did just crap in my pants, Robert Patrick.
5. The Predator - Predator
Like the T-1000 there is nothing more frightening than an enemy that can't be reasoned with or bought, it just wants one thing and one thing only, your death. You could argue that the Predator's cred was taken down a notch when paired up with a human for the buddy cop Alien Vs. Predator, but the original movie stands the test of time.
6 . Darth Vader - Star Wars
Sure he gets a little soft in Episode 6 but let's not forget the callous choke with the force first, ask questions later managing system he ruled with for 4 and 5. Prequels? What prequels?
7. The Raptors - Jurassic Park
Best evil team ever. The Raptors are stronger, smarter, faster and hungry. Trying to get a raptor to leave you alone is like my sandwich pleading for its life. I don't speak sandwich, the sandwich will die by getting ripped to shreds with my teeth. Unless the sandwich makes a sandwich whistle, but let's all just pretend that last Jurassic Park doesn't exist. These fellas were lean, mean eating machines.
8. The Aliens - Alien, Aliens, etc.
Similar to the Raptors, you just can't reason with these guys, no matter how many times you coax them with a "here kitty kitty." They just want to eat you...or lay their seed in your chest.
9. Dr. William Weir - Event Horizon
He cuts out his own eyes. 'Nuff said.
10. The Reavers - Serenity
The Reavers themselves weren't that scary, but they become gain a lot of terror from the way the rest of the world fears them. They are the only creatures I know that can make Captain Mal shake in his boots. And shake he does when he orders the town to lock themselves in a bank vault until they run out of air.