Schoolghost

http://www.kirotv.com/video/17131579/index.html


IMO It's a bug crawling on the dome of the camera. the "shadow" is just it partly blocking the light reflected from the floor. As an example put your finger up to your eye till its out of focus, no look at a light source, move your finger to obscure the light source slowly, you'll notice that its not a clean line between covered and uncovered, the light gets dimmer as more and more of the photos get absorbed by your finger.

You can do this to see "through" a pencil or a straightened paper clip.

For more information about how this works look up the double slit experiment, and the difference between coherent and incoherent light.