Rust never sleeps...
I was driving my '73 2002 and had just come off of the freeway (doing 70mph or so) to a surface road and was doing 30-ish mph. It seemed like I had hit a big pothole (but... there was none on the road) and then I heard the most horrendous scraping/rubbing sound as I felt the car droop and pull to the right. The car was getting harder to move and I was only just able to pull most of the way off the road. When I stopped, blue tire smoke was wafting out of the front-right wheel-well.
It turns out that the passenger side lower spring perch "cone" was rusted and had finally given way, suddenly dropping the weight of that corner of the car onto the bump stop and jamming the now-loose lower spring perch between the strut tube and the tire. Doh!
The scary part is that I really like to "enjoy" corners and had the spring perch failed in the middle of a high-speed on-ramp (or perhaps at an autocross), who knows what could have happened? Even if this had occured just two minutes earlier while I was on the freeway, I am pretty sure it would have at least shredded the tire, possibly severed the brake lines, or worse...
Fortunately, since it all happened at low speed while going straight, collateral damage was quite limited. One of the rigid brake lines from the caliper to the flex hose was a bit bent but showed no signs of breaking or leaking; I was thankful for the (ultimately unscathed) stainless braided kevlar flex lines.
You can all bet that, from now on, I will be doing much more frequent and thorough rust-check sessions to make sure that no other critical components are compromised. The fact that the broken strut seemed totally fine only five years ago (when I replaced the strut inserts) and showed no signs of a rust problem is further proof that careful checks need to be made more frequently. Serious rot can happen quickly, since quite a bit of water and dirt can collect inside the conical spring perch "cup", especially if the drain holes ever become clogged. I think the 2002 and similar designs are more prone to this problem simply because the spring perch is not typically replaced with the shock, so most 2002s are still using their original parts, 30 years later - lots of time for rust to do it's dirty work.
There was a happy ending. It was a sunny Saturday, I was close to a friend's well-equipped garage so the tow was relatively cheap, and I happened to have a serviceable replacement strut on my parts car so I was able to get the car back on the road the same day with no serious harm done.
I like to think of the whole experience as a gentle wake-up call from the Almighty. Check those struts!