The American Economic Association has made all issues of the Journal of Economic Perspectives available to the public without charge at aeaweb.org/to/jep. This is an excellent journal that deserves a wide readership.
A few gems:
Mark J. Machina, “Choice Under Uncertainty: Problems Solved and Unsolved,” Summer 1987. I stayed up all night reading this article when it was published in the first issue. It made me aware of the shortcomings of expected utility theory, and it introduced me to the vast literature on normative and descriptive theories of rational choice.
Hal R. Varian, “The Arbitrage Principle in Financial Economics” and Mark Rubenstein, “Derivative Assets Analysis,” Fall 1987. This pair of articles in the second issue is a good place to start in understanding financial engineering.
Matthew Rabin and Richard H. Thaler, “Anomalies: Risk Aversion,” Winter 2001. This explains why you have to look beyond risk aversion to explain many consumer choices and why you can sometimes get away with assuming risk neutrality.
N. Gregory Mankiw, Matthew Weinzierl and Danny Yagan, “Optimal Taxation in Theory and Practice,” Fall 2009. This explains the insights and limitations of the economic theory of taxation.
Ernst Fehr and Antonio Rangel, “Neuroeconomic Foundations of Economic Choice — Recent Advances,” Fall 2011. This summarizes current research on the relationship between neuroscience and utility theory.
Jeffrey R. Brown and Amy Finkelstein, “Insuring Long-Term Care in the United States,” Fall 2011. This provides an overview of Medicaid and the market for private long-term care insurance and explains the public policy challenges in financing long-term care expenditures.
Shlomo Benartzi, Alessandro Previtero and Richard H. Thaler, “Annuitization Puzzles,” Fall 2011. This discusses why life annuities should be popular, are less popular than they should be and how to make them more popular.
Justin M. Rao and David H. Reiley, “The Economics of Spam,” Summer 2012. This explains why it would be quite reasonable to impose the death penalty on spammers (my interpretation) or to devise methods to raise spammers’ operating costs (authors’ interpretation).
I have left out many equally worthy contributions. What are your additions?