Two summers prior to that, I stayed in a house in New Hampshire for a week. It was a very nice house, but the only downfall was that it was pretty close to the train tracks. Every single night, the mirror to my dresser would vibrate against the wall and make a terrible buzzing sound.
One night as the train was going by, it seemed to have been moving past my house for an extremely long time. I got up out of my bed to look out the window to see what was taking so long. The shades we had were solid material, rather than blinds with individual strips.
I could hear the whistle and the wheels chugging as if it were just passing my house when I lifted the shades to see a man looking back at me. I screamed and scrambled backwards and fell over my suitcase. I could only see him from the shoulders up, and when he ran away, he didn't even turn around. It was like he ran backwards. My cousin and I got back up and looked out the window, and there was no trace of the man whatsoever. There wasn't even a place for him to hide out there. He was just kind of gone.
Credited to Skella