This is the only ghost experience I have had, but it freaked me out.
My dad and his girlfriend had bought this house in the year of 2007. It was an old looking house, kind of looked quite tropical and had a 'tree house' feel to it. So my sister and I had visited them for the weekend, and I slept in my dad's girlfriend's daughter's bed, while she was away, because I don't have my own bed. And I was just lying there, trying to get to sleep when all of a sudden the bed started rocking. I was so freaked out, I couldn't move. I just lay there staring at the ceiling hoping it would stop and it did a minute later. I got out of bed, switched on the light and looked under the bed, but there was nothing there because I thought my sister was playing pranks on me.
So I turned the light off again and went back to bed. And it started rocking again. I went through all the possibilities in my head, it couldn't be my dad or his girlfriend because they were sleeping in the next room, and it was late at night, no one was walking around the house.
The next morning I went downstairs and told them about it, and his girlfriend said that Amy, the one who usually sleeps in the bed has had that happen to her before too... So I don't know if it was the supernatural or not... But it did freak me out.