Sunroof and seat rail grease stinks!
 

For a long time, I couldn't figure out why it smelled like old rags when I opened my sunroof. But I've finally figured it out! Turns out that the grease on the sunroof rail and the seat rails smell like a metallic dirty rag that won't even go away after dousing it with Ozium.

Does BMW have a service bulletin on this, or has anyone found a solution for it?