I was once stuck in Heathrow because of weather, eventually missing a connection in Amsterdam. I believe that the delay was about six hours, from a faulty memory. I think it was just that flights were taking off with additional gap between them, and this built up over time. Because of the missed connection, I spent a day in Amsterdam and headed off (to Japan) on the same flight next day.

I got stuck in (error fixed) Jeddah overnight, as a plane was faulty and they had no replacement. From memory, the flight was meant to depart in the afternoon or early evening, but it departed maybe 9am the next day. They didn't seem very well set up for the problem. There was a huge queue to assign people hotel rooms. When they asked if anyone would like to overnight in the lounge there, I went for that. Only about three of us did. I claimed one of the tiny rooms with a lay down couch and could sleep. There was free food and drink and generally it was comfortable. I heard from other passengers that the queue for hotel rooms lasted for hours and they assigned more people to rooms than there were beds in the room, expecting people to share beds with strangers. Even worse, anyone who had entered Saudi Arabia on a visa (as I had) was taken to a hotel downtown, and then they didn't turn up to collect them on time, causing ... stress. Also, when I had a look at the lounge film theatre the next morning, there were a lot of people in there asleep. I guess they were from my plane. I definitely think that for once I made the best choice to be an early adopter of the lounge solution.