It's actually a real vehicle. It's called the Amphicar and is a German import that was the only aquatic car to ever be mass produced. It can be driven both on land and water. I had to do a bit of searching for it so here's the Wiki page. http://en.wikipedia.org/wiki/Amphicar
Had nothing to do with the shaking, the images just came out really grainy. Even with a spotless lense, there was no difference. The one's I posted were pictures I intentionally shook to get a blurred effect.