NPR's John Burnett reports on the tens of thousands of poor Mexicans who are streaming north in search of work, with no intention of crossing into the United States. Instead, these migrants are heading for the many assembly plants in a number of Mexican border towns. In Juarez, just across the border from El Paso, Texas, more than a hundred people are arriving every day. While they can do better economically than back home, many of the migrants are living in cramped conditions, or in shacks. They're also encountering a vastly different culture, complete with mega-stores, internet cafes, and deadly drug traffickers.