Last night's film was "Paranormal Activity" which was a horror film done in a similar style to "The Blair Witch Project", with a similarly tiny budget (about $10K--suck on that, James Cameron you hack of hacks). Like "Blair Witch" the idea was that a videotape was found by the police, and we the viewers are seeing what was on the tape. A husband and wife apparently discovered some strange disturbances in their home, and the husband decides to set up the recorder to try and pick up evidence of such disturbances. Hijinks ensue, and things get a lot worse.
Now, I have to note that the film does a good job avoiding common pitfalls found in horror films. One pitfall is the "why are the characters idiots" pitfall--audiences lose their fear when they see the characters do stupid unrealistic things, like run from the murderer and hide in a closet, or go into a basement with just a candle when they hear strange growling sounds and that creepy violin music. First, this film doesn't use background music, second, the characters don't really do anything stupid. (The constant filming of everything is a stretch, as they need to explain why it's all on film, but the need for the husband to collect evidence makes some sense). They can't leave the house because (as they explain) the happenings had been following the wife around since she was a little girl.
This film got me thinking about what I would do in a similar situation--some sort of dark force or demon is chasing after one of my loved ones. My first option--get new loved ones, there are more fish in the sea--probably wouldn't work since I get attached to people easily. And weapons are basically useless against demons, so my arsenal of firearms and spears would be no good. In fact, there's only one thing that can work against a demon.
Yes, I would immediately make a pact with another demon, hopefully a stronger one who proves to be a better houseguest and isn't good at doing a title search on the souls of my family (which by that point would likely already have had several liens on them to various car dealerships). Then there'd be a little talk with the kids, about how Dad just inked a deal with a Demon who goes by some ancient Assyrian name but we'll be calling him Floyd from now on and he'll be using the spare room. Will we have to endure some loud noises from time to time? Sure, but no different from bringing in a German exchange student. I see it as a net plus.