I have a friend who has told me countless stories of his haunted houses; one of which he moved out of.
At his current house, he has a laptop in the corner of his room, and his bed on the opposite corner of the room. He has told me that almost every night since he moved in, after he puts his laptop into Hibernate mode, he would go to sleep, and wake up at 3 am with the laptop on.
One night, his laptop was on and he was logged into his computer and everything was open; Safari, AIM, iTunes, etc. His brothers were asleep as well as his mom. His door was closed all night, and he's a pretty light sleeper, so he would have heard his door open and close and the laptop turn on. Coincidence?
Also, he has told me about his mom who has had paranormal encounters. His mom was completely wasted and asleep on her bed with the light on and door open. My friend went in to shut her light off and close her door, but his mom was talking in her sleep. He told her to be quiet and go to sleep. She yelled back at him "Be quiet! They don't like it when you yell!" Then my friend went to shut off the light, and she screamed "Turn the light back on! They don't like it off.!" My friend said "...Who's they?" She didn't respond. He yelled "Who's they?!" She said "The people behind you." My friend slowly turned around, but saw no one and nothing. He ran into his room and left the light on and door open. He had to call someone to drive home and close the door and turn off the light for him. Personally? I don't like 3 am. Or ghosts for that matter.