I'll mention a couple that are more rare:
-the steering wheel buttons, particularly the volume control, rattles. i have a piece of paper wedged in there for now (ghetto), and i'll take it in to get it replaced during my next visit.
-this is a cool one - once in a blue moon, my idrive wheel loses the notchy feedback that it normally provides and i'm able to just spin it freely. after a few spins, it "catches" the gears again and i can notch it left or right again. happened about once every couple of months.