Some of my friends have watched The 4th Kind and each gave me a totally different view, majority recommended me to watch, they say it can be real disturbing, while a few called it not impressive at all, oh well everybody has different tastes anyway.
Regarding Paranormal activity honestly I am still having nightmares and at times get all paranoid and creeped out in the middle of the night or while turning off the lights before going to bed. LOL I am serious man, I've never been like this in my life, that damn movie has had some terrible effects on me ever since I watched it!
Taken the walking noise on my roof (It's been like this for like 3-4 years), and the squeaking random sounds at night in my house all contribute to help Paranormal Activity movie scare the shi**t out of me!