Another anecdote, possibly related. About 15 years ago I worked at a large nuclear installation. The office in which I worked was quite large and situated two floors above a welding workshop.
One Sunday I turned up to do overtime. I was the only person in the office. I had about 6 hours work to do, but after a couple of hours I began to feel distinctly uncomfortable. It's worthwhile saying that I don't get spooked easily (i.e. pretty much never) and it was early afternoon on a bright day. The office itself was spacious and airy and had a great view over the surrounding countryside.
After half an hour or so the feeling of vague oppression had turned to one of fear. I was having grave problems concentrating. Another five minutes and I simply had to get out of there. There was no doubt in my mind that if I stayed, I would die. The feeling was that strong. I wasn't outwardly panicking, but I had to make a concerted effort not to just bolt for the door.
I gathered my stuff and rose from my chair. At that point, the computer terminal on the desk opposite set on fire (there were no PCs in the office at that time, only these text-based VT320 dumb terminals consisting of a keyboard and b/w monitor). This didn't help my frame of mine and to be honest I was so intent on getting out of there that I almost left anyway and let the place burn down rather than spend a second longer in that room. I actually ended up hurriedly unplugging the monitor and taking it out with me - smoking and sputtering flames - and leaving it on the grass outside.
Now I have no idea what caused these bizarre events. I worked in that office for five years and had no other experiences. All I can think of is that perhaps something was going on in the workshop that created an effect equivalent to the those attributed to ultrasound, as heard about in other anecdotal tales. Certainly I didn't see any ghostly apparitions or physically impossible object movements.
One final thing (added solely for woo-ish humour value); The last thing I did before I stood up to leave was submit a batch job to run later that day. We used VMS back then and every batch job was given a unique number between 1 and 999. So yes, you guessed what number mine got - 666
It was two seconds after I noticed this that the monitor set on fire.
It just shows, however, that combining coincidences with the unexplained can easily lead to woo-ish conclusions. I have no idea what prompted this episode but I'd be very surprised if it didn't have a rational explanation, perhaps something to do with activities in the workshop two floors below, which certainly contained large extractor fans and other pieces of heavy machinery.
