The owl lighting kit has a sequencer that makes the lights flash front to back and back to front. It has a speed controller as well so you can control the sequence rate. You can get them in differetnt colors as well.

Grant "G" West did a kit similar to this on his trailer and did a post on WW a while back.

http://www.youtube.com/watch?gl=CA&hl=en&v=4cARz9ABSBI