On a recent flight I had an Asian gentleman industriously pick his nose throughout the flight. He would 'dig in', remove something-- look at it closely, then rub it on the armrest. I did attempt to ask him not to do that, but he didn't understand english and just looked at me blankly. Luckily it was a short flight, and I ended up keeping my back to him and stared out the window. (I then later found out, in some cultures this is not deemed inappropriate public behavior)--just like spitting in the street etc.
