Also, when it comes to boxing up the leftovers (No they don't have Chinese-take-out-shaped boxes here), it's really rude to do it unless your only with your family. If you go out on a date and ask to box up the rest of the food, it means that you care too much about money and little things and not enough about the person you're with. Again, may be because of the shared dishes phenomenon.
When you eat with a bowl of rice with others at a restaurant, you use your chopsticks to take a piece from the communal dish and eat it over your rice bowl, sometimes dabbing it on the rice to make the white stuff exciting. I do prefer to just spoon the sauce over my rice, but that's not really how it's supposed to be done.
My favorite: when you're eating soup and/or noodles, slurp as much as possible. It means you're enjoying it. I'm going to miss noodle soup the most.