9. Flying glasses.

Last week I was in the kitchen with my wife making the dinner. We both had a glass of cola and she put her glass down on top of the fridge.
Now in order to picture the scene properly, I need to give you the layout of our kitchen. Its about 12 feet long and six wide - a typical galley kitchen. The fridge is near the door leading to the hall at one end which is in turn directly opposite the back door at the other end.
So, she put her glass down on top of the fridge and we went into the living room.
Minutes later we hear a smash and we go to investigate. Her glass is lying shattered on the floor by the back door twelve feet from where she put it.
Our first thought was that it was the work of one of our two cats, but it turns out that they were asleep upstairs on our eldest's bed. The kids were in the living room with the dog and the kitchen was empty. So what had caused the glass to jump from the centre of the counter top and to smash on the floor at the other end of the room?
It appears to be that time of year again.