In answer the question about "seances" at historic house museums --
Here at the Charles Gates Dawes House in Chicago (1895), we've teamed up the past two years with a magician for a program we call "Haunting History." He leads visitors on evening tours of the house in which something magical and/or supernatural happens in each room. In one room, for example, he has a visitor choose a word from a book and then a mysterious person in the next room reveals that word on a Ouija board. There are about 7 rooms in all and 7 different magical events. It ends with a recreated "seance" in the master bedroom. He gives a nice synopsis of the history of 19th century seance fad and then the group conjures up a spirit who makes things happen in the room -- lights go out, objects move, strange handwriting appears.
What I like is that he weaves a great deal of history into the program. What he likes is that unlike storytelling in a haunted house, where you listen to things that happen to the characters, the visitors get to participate in the story.
It's a nice change, too, from the typical haunted house with zombies jumping out of closets. It's quite eerie and spooky, but more in the sense of how you feel when you're reading alone at night and suddenly the lights go out.
And what we both like is that it was a great fundraiser for both of us. We split the profits with him, so we didn't have to pay him, and he put a lot of effort into publicizing it on top of our efforts. Worked amazingly well all around.