Ok, I remember watching a movie when I was little with something's like facehuggers. Or they looked more like the things from Half Life, because they had tooth and looked like a pancake :D Basically it was something like this.. group of people, and this things kept coming from nowhere, flying to people faces, or other body parts and attaching with something like tentacles under the victims skin. But as I recall, later in the movie a alien guy appeared, and it was revealed that he is tossing the creatures.. I can't remember details or anything else, except a scene where a pancake attached to the leg of one guy, a pancake attached to the face on other guy.. and a pancake on the windshield of a car, trying to chew the window :D and a pancake attached to a house..

Without Warning (http://www.imdb.com/title/tt0081764/)

Thank you SO MUCH ! 15 years of wandering..

Glad to help.