Strange rattling noise from under car

danelonson

As I was driving home today with the windows down, I noticed a rattling/clanking noise that comes from the passenger side under/side of the car. It sounds to me like a thin metal plate vibrating and hitting something. As I drive normally I don't hear anything but any slight bump on the street (such as lane reflectors) and I hear it. If I'm on the middle lane and go over a reflector with my left tires I don't hear anything but on the right I do. I also noticed it on the highway as I went through a bridge that has slight bumps I could hear it really loud.
I know it's very hard to determine what this could be without you guys actually hear it but any ideas would be greatly appreciated. Thanks!