I have 2 unexplained experiences. 

Once when I was 5 maybe 6, so mid 80's I had a toy box shelf thing that had a sliding door on it.  It had a hole to put you finger in the door to slide the door over.  I had some plastic toy bolts, I stuck one in the hole, something started rattling it around.  Lasted about 4 or 5 seconds.  I ran out of that room, never would go near that box in my closet again.  Still sticks in my head to this day. 

2nd experience was late summer of 2007.  Was fixing up the old farmhouse to move into.  It was really run down by the last tenants, almost unlivable.  Did a lot of work, came in one Saturday morning.  There was a fan between the kitchen and dining room.  Just after I walked in the front door the fan turned itself on.  There was about a 7 year old, would have been my great aunt that passed away here.  I would say maybe that was a helpful one, wanting me to get the house fixed back up to the way it was.

Edit:  I thought of one more.  Really hard to explain.  I was still in high school, It was before school at my moms house.  I was the only one in the house as everyone else was gone.  I heard some kind of angelical music, last a few seconds.  No idea where it came from.  My mom has explained something similar to me one time before that she heard.  She has a lot of angel porcelain figurines around, none make sound, didn't sound like a speaker, it was room filling sound.  Not loud, but just everywhere.