The case of the haunted hair dryer

The other night I woke up at 1:44am to a constant high pitched buzzing noise. I am no Nancy Drew, but the noise was really annoying so I got up and went into my bathroom to investigate. My hair dryer had somehow turned on (I leave it plugged in, but I know it wasn't on when I went to bed that evening) and apparently it had been on long enough to warm my bathroom by an additional 10 degrees or so.

Very weird.

I flicked the switch a few times until I was sure it was off and went back to bed.

Just as I was falling back asleep, I heard the hair dryer turn back on.

Now we're talking freaky.

I got up again, unplugged the blasted thing and brought it into the bedroom with me. It took me a while to get back to bed afterwards as I pondered the cause of this anomaly: I figured it must have been caused by a weird power surge or something. The hair dryer is pretty old too. Because if it was an intruder, why style your hair before robbing/attacking me? And if it was something of paranormal origin, why not turn the TV on instead? Or the lights?