@rebelfighter: Yep. A local ghost hunter in my area was on public radio for Halloween talking about cases like that. He mentioned that EMF from old electronics can have very strange effects at times, even including the sensation that you've been touched. I find that easy to believe, because I've worked in places where I was required to carry a radio, and I always always felt when there was a call about to come in. My mother, while mourning for my dead father with the old tube TV running for hours, said she felt an angel's hand on her shoulder.
In very very rare instances, they're stumped and offer to do a ritual to "expel" whatever's there, but even then, he noted that the ritual is a psychological placebo.