You know, I'm beggining to think its my clutch now too. I thought it was a loose exhaust pipe cause it only rattles when I'm at idle or at low rpm's.
It started after it bottomed out on a speed bump going about 15 mph over it, pretty slow but still bottomed out, but lately I hear alot more often.
I had it checked when I recently had my exhaust installed, they banged from the middle to the engine bay to find any loose hangars or anything that rattled for that matter. They fould nothing, but like I said before, I hear it more and more. I'm hoping I don't have to change clutch already!