Since everyone seems so interested inth e subject, I'll tell some great Disneyland stories!
These are all from the Haunted Mansion because that is the only one I know of.
Well, for background, rumor has it that years ago, a woman approached Disney saying that her sons had been killed, and that he had absolutely loved the Haunted Mansion, so she had wanted to spread his ashes in the Mansion. Disneyland, of course, said NO. So the woman got on the ride herself, and at some point turned and dumped the ashes on the ride herself. Whether this part is true or not, I can only guess. But that's the story.
Anyways, weird stsuff started happening. Once, as guests were getting off the ride, they reported to the CM at unload that there was a little kid running around the ballroom scene. So the CM sends security in to look: nothing. They never found any clue that the kid had ever even been there. Similarly, guests have reported coming off the ride, late at night when it's quiet, and seeing a little boy standing alone at the exit (at the top of the moving ramp) and crying. Some have said that when they asked him if he needed help, he acted like they weren't there. Some have even said he disappeared. Of course, by the time they tell a CM about him and the CM goes to check it out, he's long gone.
Well, it gets really creepy then. This part of the story I have confirmed with a friend who worked at the Mansion. I mentioned these haunting stories and he freaked out, sayinig this had actually happened to him... he was glad to hear he wasn't going insane.
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Late at night, they will often only run one stretch room because it gets so quiet. That means that between groups of guests, the CM at load is all by themselves, just waiting for people. Well, one CM was waitinig for the next group, thought she heard a child laughing. She figured the next group had arrived, and kids were coming - but no one ever showed up. Then, she saw something move out of the corner of her eye. Turning to look, she saw no one there, so she put it off as her imagination. But she saw it again, and again, there was no one there. Well, about this time she starts feeling a cold chill, and is getting kinda freaked out. All of a sudden, she feels someone put their hand on her shoulder - but there's no one there. She screamed and ran out, and told management she would never go back to work in the Mansion again.
My friend had a similar incident (although not as intense) at Grad Nite. It was really late, so no one was going on the Mansion at all. He'd been at load, waiting for another group, for about half an hour. Well, like the other CM, he heard a kid giggling and thought maybe someone was finally coming, but no one showed up. He knew that since no one had gotten on the ride in the past 1/2 hour, that everyone had gone through and there was no one on it at all, so he called unload to see if there was anyone else there. Nope, only the other CM, who had also not seen anyone in a long time.
One of the other "hot spots" in Disneyland's Mansion is one of the Stretch Rooms. I can't recall offhand which it is, but I THINK it's the one you go into if you go straight when you enter the building, as oppose to going left. Anyways, CMs have reported having bad chills in that room when it's quiet. Now, after guests are dropped off, the room goes back up, much faster and without the light/sound effects, etc. It basically justs goes up like a big elevator, nothing special. This I can confirm, as my friend and I rode up and down a few times just for the fun of it.
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On occasion, though, I've heard reports that the soundtrack would come on, and play BACKWARDS as the elevator moved back up, and all the effects would go off. Some CMs have even said that they've seen personal effects get shot across the room seemingly by magic.
Long story short: weeeeeeird place. I took a photo one night a couple of years back, just to have a nighttime Mansion photo. Well, I got the prints back and there was a lighter, circular blob in it. Many, many people have come to me and said it is an orb, though I have not personally ruled out glare. But who knows?
-Kirsten