I've never spent an unplanned night out, although I came close once when I went off on a long dayhike without my headlamp. I fortunately got off the steep, rough section of the return trail while it was still light, and had only a mile of level trail, most of it in the open and therefore lit by a half-moon, to get to my car. That was close, because I definitely would have stopped and stayed put on the steep, rough trail section had I been only 10 minutes later.

I was quite well prepared to be out overnight, though, and would have finished the hike out the next morning in good condition.

I keep thinking I should spend a night out with my "Ten" Essentials, and i may yet do that. Of course it needs to be a cold, soggy, windy, and otherwise miserable night for full effect! Unfortunately there is a lot of difference in being prepared to spend a safe but uncomfortable night when necessary and deliberately going out and doing it--I'm a bit short on will power for the latter!