I've posted recently on How high is U.S. income inequality?  I followed up with posts on about Causes of Inequality: Supply and Demand for Skilled Workers and How the U.S. Has Come Back to the Pack in Higher Education. Here's one more metaphor on the subject. Back in its January 20, 2011 issue, the Economist magazine had one of its wonderfully readable surveys that touched on many issues of inequality, called "A special report on global leaders: The rise and rise of the cognitive elite." The entire article is worth reading, but here is a striking way to visualize U.S. income inequality. 
"Jan Pen, a Dutch economist who died last year, came up with a  striking way to picture inequality. Imagine people’s height being  proportional to their income, so that someone with an average income is  of average height. Now imagine that the entire adult population of  America is walking past you in a single hour, in ascending order of  income." 
"The first passers-by, the owners of loss-making businesses, are  invisible: their heads are below ground. Then come the jobless and the  working poor, who are midgets. After half an hour the strollers are  still only waist-high, since America’s median income is only half the  mean. It takes nearly 45 minutes before normal-sized people appear. But  then, in the final minutes, giants thunder by. With six minutes to go  they are 12 feet tall. When the 400 highest earners walk by, right at  the end, each is more than two miles tall."
 
