The strangest experience with crying for me was landing in SYD after flying from LAX not very long after 9/11. Once the plane landed people clapped, including me - so happy to be back in Australia, and people cheered and quite a few had tears of joy.
However, the most upset I have been was leaving Australia to go back to DC for work after Christmas, having to leave my mother who had terminal cancer and not knowing if I would see her again. I was seriously hoping that the plane had a minor fault which would mean another day with her. When the wheels lifted off I was crying quietly, thankfully in I was the only one in my row.
Fortunately I was able to return and spend the last two weeks of her life with her.