Interesting thread - I've got a rattle, really high frequency that almost sounds like a bumblebee, coming from the fuse box area or somewhere under the steering column.
I'll have a look at the bolts.
Also something in the back rattles. I think it's the rear bench, like leather on leather. Can't suss it to save my life though!
Oh and the worst one... The driver's seatbelt adjuster, on the b-pillar. It constantly rattles, and it's right in my ear. Tried moving it to different heights, no joy.
Sometimes wonder if my old mk4 was better built!