Paul Krugman is a professor of Economics at Princeton and a columnist for the New York Times. I love reading Krugman's columns, but he got his Nobel Prize for his work on international trade. His work simplified much of the complexity inherent in explaining international trade. And it looked at international trade in a new way, explaining why Americans would buy Volkswagens, while Germans would buy Fords.
Here's a link to the lead story in the New York Times. http://www.nytimes.com/2008/10/14/business/economy/14econ.html?partner=permalink&exprod=permalink
Conservatives tend to dislike Mr. Krugman because he has many liberal ideas about how to make the economy work better for all. Even though I tend to be fiscally conservative, I think Krugman makes a lot of sense on many topics. But I did major in economics in college.