Do/Do Not!, Hong Kong
Tipping in Hong Kong is very important and almost a way of life. The service staff expect nothing less than 10% of the bill even when a service charge has already been levied. Cab drivers tend to mark up the fare to the nearest HK$ and if not, will appreciate a little extra.
Leaving chopsticks sticking vertically into the bowl is a bad omen. This resembles incense sticks in a bowl of ashes, a sure death sign.