1. Stomach flu (aka, stabbing gut pains, frequent bathroom trips, nausea, and all the other unmentionables associated with it)
2. Screaming babies taking turns in almost perfect alternation to allow not one minute of blessed silence.
3. Spilling a cup of steaming hot tea on your crotch that brings back memories of wetting your pants to only have it later turn into freezing cold sogginess for 3 hours of flight time