Chris and I had a scary movie marathon on Halloween. We watched 30 Days Of Night (meh), My Name Is Bruce (loved it!), Zombieland (loved it!) and Paranormal Activity.
Paranormal Activity is very low budget ($14,000) and utilizes the POV hand held camera technique. So if you didn't like Blair Witch Project or Cloverfield because of that then you probably won't like this movie either although most of the time the camera is sitting on a tripod so it's not too shaky. There are no big special effects and most of the movie is just watching the things that happen while they're asleep.
It was very, VERY creepy.
From talking with people, they either love or hate this movie. I found the way it was shot to be very atmospheric. The suspense was almost unbearable and I was literally on the edge of my seat, waiting for something to happen. For a movie with almost no special effects it was pretty scary. Now, I'll admit that I had trouble going to sleep that night but I'm happy to report I didn't have to sleep with my light on. If you like scary movies I suggest you give this one a shot.
FYI, there are two endings. The first one from the 2007 release of the movie and then the edited ending that's currently being shown. I had the opportunity to view both endings and I personally found the original ending to be much better.