Poltergeist scared the shit out of me when I was younger too. Not a lasting fear, but I definitely had some nightmares that evening.

Nothing has really ever happened to me that's sparked a lasting fear over anything in specific. However, when I was a kid I used to hallucinate like crazy whenever I had a fever. I remember seeing these dark geometric shapes moving extremely slowly accross my pan of vision. They moved so slowly that they would barely go anywhere... just enough that I was able to tell that they were not 100% still. As I remember my eyes would be open, but that is all that I could see, with some droning fucking noise that they made. In those moments that is all that existed and it really scared the fucking shit out of me. My dad used to sit in my room with a cold washcloth over my forehead and try to comfort me while I was literally screaming in terror. One time I burst out of my room to find my mom and dad on the couch, and as I reach them they shapeshifted into demonic forms. I don't know where these things came from internally... but once in a great while, I'll perceive those same shapes, moving but not going anywhere, usually when I'm half asleep. Very, very rarely. And once I realize that I'm consciously aware of it happening, it stops. Doesn't really frighten me at all... I'm just perplexed by it, and why it's there in my subconscious.

^Poltergeist scared me shitless for weeks, too. It didn't help that we were told a year before that the place where we lived was built on an ancient Hawaiian graveyard.

this scares me because i had similar hallucinations when i was a kid. whenever i had a fever i had the geometric drone noise visions as well as pasta or yarn shapes moving like worms or snakes but gigantic never ending piles of them with a weird clashing gnawing sound. so strange and i cant really understand it to this day.

first time i was scared was when i yelled and kicked and screamed to watch alien with my dad and brother, then had nightmares for weeks. now i love it. strangely poltergeist didnt scare me when i was little, but i scared my parents when i said "they're here"

I saw Akira when i was 5 and that shit messed me up for awhile. It also gave me a fear of japanese animation.

It seems that these types of hallucinations associated with high fevers are pretty common.
I too experience geometric patterns and buzzing noises when I've had high fevers in the past.
When I was around 10 or 11, I had a high fever and couldn't sleep so my dad let me stay up and watch a late night movie on this new channel called the home box office.
Little did my dad know that the original Friday the 13th wasn't appropriate for a sick 10 year old to watch!
After the first few kills, I think he just sort of gave up and let me finish it.
He did state that I couldn't tell Mom what we had watched. Haha!!
That didn't work out too well for him, as I believe that I slept in their bed that night.
And as any of you guys/gals out there with kids know, it's never a restful sleep when your bed gets taken over by a sick/scared kid.
Now I want to go home and re-watch the original Friday the 13th again.

Someone mentioned the Wizard of Oz. I was 3 or 4 & my mom got me all excited about it. The flying monkeys freaked me out & I ran in my room & refused to watch the rest of the movie. I would not watch again for a few years.

Now I wish I had a pet flying monkey.

Aside from that, I showed Poltergeist to my son when he was 10. It scared the shit out of him. He was OK, but I felt awful.

Between Poltergeist and Pet Cemetery I a hard time walking in front on beds at night time as a kid

My own dreams and thoughts scare me the most and I dont recall anything tramatizing from my childhood.

I used to have similar experiences. Rather than geometric shapes mine were three tiered organic blobs. Whats most weird is why dont we have those visions when we get sick nowadays?

Although I was quite the imaginative kid, it was more of the realistic movies that scared me the most. The type that you KNEW could be real & imagined laying just behind your neighbors front door or under that tarp in their backyard, while riding your bike around the neighborhood. "The People Under The Stairs" was one of the cake toppers. I own it now, but it still gives me chills, nothin too serious though... Speaking of this stuff, I'm currently watching a Nightmare on Elm St. Marathon on Syfy. Is there a reason they're leaving out #3?! It's one of the best of the bunch in my opinion.

just saw this video and was reminded of this thread
http://www.youtube.com/watch?v=oh87njiWTmw