Mike Marshall seems like an interesting guy that no one will listen to. Very strange-looking delivery but if it's effective, then I say Mark Prior should use it. Maybe he would actually pitch past Memorial Day.
This is pretty neat. Link includes video, for you folks so inclined to visit the link.
My first thought when watching the throwing motion is that it has the tendency to reveal to someone on second the type of pitch that is coming based on the angle of the wrist...