With respect to his views on the global financial crisis, and the causes of the implosion in the United States, we have his recent book: Fault Lines: How hidden fractures still threaten the World economy, Princeton University Press 2010.
This is a distillation of his views on the origins of the global financial crisis that originated in the US in 2008 and how it was not a single one-off event but the result of several deep and systemic problems (that he calls "fault lines") in the world economy.
Although Rajan has often suggested that he was alone in warning about these problems (most famously in a paper he presented at a conference of central bankers in 2005) this was actually not such an unusual argument even before the outbreak of the crisis.
Apart from many economists in the developing world, heterodox economists even in the US such as Jan Kregel, James Galbraith, Nouriel Roubini and others had been making these and more detailed points with much greater clarity for some time.
In any case, students of economic history and financial bubbles would have found great prescience and applicability to the present, in the analyses of financial cycles in the work of Charles Kindleberger, Hyman Minsky and John Kenneth Galbraith, whose works Rajan surely would have read.
Joseph Stiglitz had identified exactly some of these forms of asymmetric information and how they would operate to create boom-bust cycles in financial markets several decades before.