god knows you're right about rattles driving you nuts.

I've had one in the back right quarter panel that to this day I've been unable to track down. Very fustrating problem. I also have 3 distinct rattles coming from my dash. I have the "run of the mill" high pitched rattle when sitting at idle. The fan rattle when I've got it turned up, and then under heavy acceleration I've got another rattle that I haven't quite traced down to being in the cabin or in the engine compartment.

Its definitely driving me bonkers though, so I feel your pain.