I was inspired by King Aquamentus with his "scariest video game moment" thread... It got me to start thinking about my fears outside of video games. So... what freaks you out IRL?
For me, it's aliens. I don't even really believe in aliens (okay, I believe there is probably extraterrestrial life out there - visiting this planet is another matter entirely), but the thought of aliens coming along and beaming me out of my bed to do horrible experiments on me scares the crap out of me. Not often, but very rarely, I've even had nights where I couldn't sleep because the thought scared me so bad. I don't know why - probably watching too many shows about UFOs as a kid (to say nothing of the way I pretty much raided the paranormal section of the local library as a kid). But it's like - I get why the idea scares me so bad, but I don't know why it scares me even though I know it probably can't even happen. I don't believe in alien abductions - but I'm afraid of them. It's a weird disconnect. But yeah, as a corollary to that, I'm also afraid of Grey Aliens - the bug-eyed freaks just unsettle me on a primal level.