You hear the one about the guy who is so fat he doesn't have an address. He has a zip code! How about this: Yo mama so fat when she walks outside in a yellow dress, people yell "TAXI!" I'm guessing New Yorkers hear a lot of fat jokes, since more than half the people who live in the city are overweight or downright obese. I didn’t know that until I read the New York Times today. So the mayor, Michael Bloomberg, has come up with a plan to fight the problem: He’s going to ban “the sale of large sodas and other sugary drinks at restaurants, movie theaters and street carts, in the most ambitious effort yet by the Bloomberg administration to combat rising obesity,” as the Times explained it.