^Ultimate Slow motion: A group at MIT, the "Camera Culture
  group", have created a camera with a TRILLION frames per second
  speed. Here is why it is mind-blowing: When you look at yourself
  in the mirror, you don't see yourself "NOW', you see yourself as
  you were about a billionth of a second ago. With this camera,
  you can capture the light as it bounces from the LIGHT, to your
  FACE, to the MIRROR and back to your face. As you watch this
  video, especially notice what happens at 1:25: You can see the
  alien by itself, then you can watch the image of the alien in
  the mirrow SLOWLY APPEAR. What you think is instant is not
  instant at all.^