Once when I was babysitting for a neighbors kids oh so many years ago, shortly after the kids went to bed I heard some strange noises in the kitchen and went in to see several of the cabinets had opened. I shut them, went back into the other room, and sure enough- that sound again. There they were all open like before. By the third time this happened I was pretty terrified (well I was 16). Was it a ghost or was there some explanation? I can't remember if I told the parents what happened when they returned, but I'm sure I never babysat there again.
In honor of the upcoming holiday, here's a link to some creepy architecture and homes. I'd love to hear your personal haunted house story.