1) I'm afraid that someday society will have sunk so low that it will be illegal to read, to write, to play music, to think "too much," to be odd, or any combination or variation of those.
2) I'm terrified of the thought of drowning. When I die, I want it to be quick and relatively painless. Just thinking about all the possible stress involved freaks me out too much.
3) I'm afraid of being lured into a false sense of security, only to be metaphorically abandoned with no explanation whatsoever. That's probably one reason I have yet to look for love; I've heard too many sob stories. (another reason is simple: I have barely enough time to eat, get a decent amount of sleep, get an adequate amount of time tickling the ivories, and get all my work done in the span of 24 hours)
4) Mind control. It sounds innane, but the thought of someone/something remotely controlling an organ that we don't fully understand just sends shudders down my spine.
Even something as small as the idea of (almost) everybody going "Kills 99.9% of germs"-sanitizer-crazy because they believe all germs are going to kill them, the whole mass-influence thing (in my book, it could be a form of mind control; I'm not saying it is, but it could). I'm no slob, but I understand natural selection; doesn't anybody wonder what happens to that .01% that survive? Mindlessly following the herd like that just drives me crazy, and I'm afraid that the power of mass influence will fall into the wrong hands.
Or, at least, in worse hands than it already is.
5) This is a more odd one, but I think I'd get all weirded out if was laid on my back, restrained, a fairly bright light directly over my head, and at least one person standing over me. It may "help" to freak me out more if I all I could see of said person(s) were his/her/their eyes. -shudders at the very thought- I have no real reasoning for this, but whenever I imagine the situation (and I have a fairly vivid imagination, overactive, if you will) I get all nervous inside.