I'm waiting on someone to create a "Worst Cable connection you ever successfully repaired" thread.
Haven't been able to find a close enough pic to explain - yet.
That's easy. Solar battery cables to car batteries. Had to use steel baling wire and squeezy clamps. It was one of those "This has to work right now and how you do it is of no concern, just get this thing running. If you have to carve a new connector from your own jawbone, fine, get it working." The repair held for months.
BNC antenna connector was a close second. The four leaf springy male inner prong was busted. Shoved the remnants of the prong back in the hole and tightened it down. Worked for a few hours while we could get a replacement.