While waiting for his flight, a buddhist monk orders a bowl of tofu in the airport's restaurant.
"What would you like to have on it?" asks the server. "Nothing," replies the monk. "I require little."
The server gives the monk his bowl of tofu, and the monk pays with a $20 bill. The server takes the money, puts it in his cash register, and closes the drawer. "Where is my change?" asks the monk. "Change comes from within" replies the server.