Optics

I was drinking a glass of water in the kitchen, and set it down on the counter.  Turns out the sun was shining through the window on to the counter, and when I looked down, I was amazed at what I saw.  The glass with the water in it was functioning as a lens, and it focused some of the light into a bright little triangle.  Meanwhile, other parts of the glass created interesting shadows on the counter.  Who knew you could get such interesting things from sunlight and a glass of water!