What it says on the title. Mine was when I was 12 and I lived in a very haunted house which had some weird activity going on, like things moving out of place and pets freaking out. I was sitting in the computer, alone in the house, and suddenly I see a shadowy figure on the screen, just some meters away behind me, thinking was my mom I turned around and there was nothing, but the room had turned extremely cold suddenly. There was nothing behind me that could have been this shadow.
I guess a better way to describe it was that she was at the foot of my bed. I was walking back into my room from the bathroom, and I see her in the moonlight. As she turned to look at me, she just faded into nothing.