Okay, I'll play...at my own risk:)
This is embarrassing, a little the wrong side of stupid, and I was lucky. The event in question occurred a long time ago. I was in college. I was poor. I thought I liked to improvise gear.
This involved an ice climb at Poko. I don't remember which one and I can't figure it out. It's broken into two pitches, the first is a short waterfall. The second one is a lower angle, a little thin and looks sort of alpine. My belayer led the first pitch and I started up the second. I had a zero and a northwall and step in flexi crampons I'd attached to some old leather alpine ski boots. Surely, you can see where this is going....
Anyway, it's short pitch. I safely made it most of the way, about 30 feet. I placed one or two screws in that distance. And it was fun. Suddenly I lost my footing, seemingly out of nowhere. When I looked down, I saw that one of my bright red flex crampons had fallen off my boot. So I hung on one arm and tried fixing it. Once. Then it fell away again and the bail popped off the crampon completely. Not good at all.
I might have tried hopping up on one foot once or twice, don't remember now. Whatever I did it wasn't working. So I dug in my tools, put some kind of x knot on them and told my belayer to lower me fast. Even though those tools dig in better than most, the ice was brittle and one or two inches thick buried under loose snow. The tools slowed me down for something like--1 or 2 seconds--then I slid down the rest of the way. Landed in a little snowbank unhurt and a little ecstatic. A little surprised, too. Well there were a couple of crampon scrapes:)
I don't improvise gear now. I was very lucky not to hurt myself pretty badly that day. Stay Safe!