The "ART" of the slow exposure

While we were driving to and from the Gateway Arch last night I was able to sit in the back seat and experiment with some slow shutter speeds and the lights of the road. Sometimes I would start the exposure and we would go over some bumps (Bottom two photos). The effect is these stunning abstract photos with naturally drawn lines. I think that the dotted line in the lowest photo must be from a blinking construction barrel. When we were not going over bumps the effect is a sleek light drawing like the top two photo's.
I LOVE these pictures!