Ok, I've got one. Not BMW, but falls in line with "Boy, am I ever lucky I know how to fix stuff on a car" theme. Few weeks ago, I was driving my Austin Healey BJ8 with the Old-Guys-Who-Drive-British-Cars-Club here in BC. Healey's, Triumph, Rover, Vauxhall, TVR, Morgan, Jaguar, well you get the picture. Club had invited Citroen Group for some variety. All was going quite well, and just after a long decent from quite the hill, I approached a stoplight at the freeway. Stopped, then felt brake pedal was kinda, well, not normal. Thought carpet had somehow gotten jammed up under pedal, but how? It is a very heavy Cocomat. Sun was in my eyes, but when I looked down I thought I saw something shiny on the carpet. What was that?
Light changed to green, off I went, to next stop light. Calmly geared down to very slow and thankfully dialled-in handbrake brought car to rest. Started off again, same sequence....all the way home, about 10 km, so not far. Once home I reinstalled clevis pin and new washer and cotter pin from master cylinder to pedal, and all is normal again.
Owned this Healey 50 years, not much we haven't been through! Happy I have experience to draw upon.

And happy none of this stuff scares me anymore, it is just old car bonding! Mike