Various family members and I have had encounters with a being in our house whom we affectionately call "Shadow Man."
The first encounter was late one night when my brothers and I were up watching television. For some reason, my older brother and I both happened to glance down the hall at the same time, and we saw this shadow crossing the door jamb of my bedroom, completely blocking out the white paint. It looked to be a man about six feet tall crossing from my bedroom to my parents' bedroom, so we both also thought it was my father. My parents' bedroom door didn't open, however, and we both sat there staring at one another and straining to hear the sound that never came.
On a separate occasion, my mother and I witnessed another similar apparition crossing from my bedroom to hers -- and in fact, Shadow Man's activity seems strongest in those two rooms. He's been known to change my and my mother's radio station during the night. We think his silent commentary on our taste in music is quite charming.
On another occasion, my mother was reading a book on ghosts, ironically, and the book stated something to the effect of spirits sometimes possessing household appliances. She was saying to herself what a load of hooey that was when the washing machine turned on. It started sloshing and filling with water at the same time -- which it did NOT do in any of its normal cycles. She unplugged it.
Another time, she was brushing her hair in her bathroom when she felt a hand on her shoulder, as if someone was trying to get her attention. Now, you have to understand that the bathroom in question has a mirror that takes up the entire wall in front of the bathroom counter. No one could sneak up behind my mother in that bathroom. Yet when she felt this hand touch her shoulder, it was so very real that she turned around behind her to look!
Shadow Man woke my stepfather -- who doesn't believe in ghosts at all -- from a sound sleep by shaking his leg. He sat up and said, "Who are you? What do you want?" The next morning, we told him it was just Shadow Man checking him out to make sure he belonged in this family.