Steve Greenhouse writes a useful article on the economic & cultural implications of the Wal-Mart system:

We already know that Wal-Mart is the biggest retailer. (If it were an independent nation, it would be China’s eighth-largest trading partner.) We also know that it is maniacal about low prices. (Some economists say it has single-handedly cut inflation by 1 percent in recent years, saving consumers billions of dollars annually.) We know that its labor practices have come under attack. (It charges its workers so much for health insurance that about one-third of them do not have it.)