This happened a few years ago, in the middle of the day when I was working from home in a small city in central Sweden. My work station was in the living room, at the far end corner of the room.
I was home alone, working by the computer with my back turned to the room behind me, where my son had days before built a Lego tower. It was a tall and sturdy construction, which had been standing there untouched for several days.
All of a sudden I saw a fast, dark shadow pass in the corner of my eye on my left side, it was as if it came from behind me and "went into" the wall next to me. A split second after I became aware of the shadow, the Lego tower behind me crashed down to the ground with a loud bang. I had no windows open since this was in the middle of freezing winter, there was no draft what so ever that could have pushed the tower over. It had been standing proudly in its place for days - it was as if the movement of the shadow I saw had "blown it over" in its path. If anything, it blew my mind. After that, no Lego towers were left standing over night after play time was over in that apartment.
Battery toys in my son's room would also go off on their own at times, and he would not sleep a full night in there for the whole time we lived in that apartment. He was very young at the time, and it could just be due to feeling uncomfortable sleeping alone in there and nothing to do with supernatural causes. Other than that, we really loved that apartment and lived there for many years.