I saw this and I knew someone out there would have a place for it in their haunt! Seems like an interesting make and take idea.
http://youtu.be/BpAvfKGI5W4
Wouldn't it be cool to have a phone ring and when your guests pick it up they get ghostly voices or creepy sounds? Or something really scary like a recording of Judy Garland?
I was thinking that this obviously need not be limited to a phone - MP3 players inside old radios or picture frames are obvious, and certainly old hat, but the phone provides a unique level of interactivity. What if it was wired to ring and ring whenever the receiver was in the cradle? Better still, what if the ringer was wired to a motion sensor?
Is there some other application I am not thinking of?