lol I've always loved dark, macabre images, but have to date only created one myself. Sometimes I add too much and end up scaring myself silly.
I created an image for a competition about a year back. Basically all I did was create a room scene. You could see the moon from the window, and i believe there was a chair in the room. That's what you noticed first, until the ghost hit you.
I created a ghost using a model, a few brushes and effects, and then faded her into the image. I then added cold filters to the image, concentrating on blues mostly, and the effect was haunting
(pardon the pun
)