EDIT : ^ OMG thats so creepy !
I almost forgot my mum told me that when she was young she had a very realistic experience of a black figure sitting on her bed and staring at her. She woke up screaming and there was a dent in the bed where the figure was sitting. The next morning she found out that her gran had died. With hindsight my mum still think to this day that it was her gran comming to say goodbye to her.