D&DChick - 'Beast of Caerbannog' from Monty Python and the Holy Grail.
Ferret - 'Creepy Monsters' from Scooby Doo.
Krishnath - 'Gremlins' from Gremlins.
Geocorona - 'Cyclops' from Seventh Voyage of Sinbad.
Clay_more - 'Predator' from The Predator.
demiurge1138 - 'Godzilla' from the japanese Godjira/Godzilla movies.
Omata - 'Cenobites' from Hellraiser.
Andrew D. Gable - 'The Thing' from Who Goes There? and John Carpenter's The Thing.