Earlier this year I got caught by fog (not unusual trying to get back to JER from LGW). Originally pushed back at around 14:00 and the pilot advised we had extra fuel in case we needed to circle. True to form got to JER and had to circle for a good half hour before giving up and turning back. Got back to LGW and kept on the plane as they hoped the fog would clear. A couple of hours later took off again only to get back to JER circle for another half hour and return to LGW for the second time. Finally off the plane at 22:00 for two nights at the Sofitel on BA. Not ideal after flying in from Seattle and needed back at work.
Also had a diversion flying AA from SFO to LAX On some ancient 767 or similar. Warning light indicates a fire so diverted to Bakersfield to be met by fire crews and media when deboarding. Quickly hired a car to try and get to LAX to make our connecting Qantas flight to Melbourne but no joy.