When I was a kid, my parents and grandparents had a penchant for making me watch 80's horror movies and some of the older "classics" such as The Omen, Nightmare on Elm Street, JAWS, Friday the 13th and the like. While most of them I got away with not being afraid of them, there are two that really creeped me out to no end. One was JAWS, and as an adult it still sticks with me.
I FUCKING HATE SHARKS. Not fear them, absolutely hate them with borderline genocidal tendency. I see a shark, I want to kill the fucking thing. I went on the ride at Universal Studios in Orlando, FL and came out of it wanting to murder the ride operators and the designer.
The other thing was Texas Chainsaw Massacre, the only thing I remember is the scene where Leatherface pops out of a freezer. Ever since then I don't like those types of freezers and get a little edgy near them.
Also I hate clowns with a passion. Not fear, again like the sharks I fucking hate clowns and want to kill them.
Thankfully I have high impulse control techniques and have refrained from killing any in my life so far, but I have punched a few for getting too close. Also I've got in a few fights with ICP fans... but thats for other reasons besides the clown thing. I think "Juggalos" are some of the dumbest cult followers on the planet.