1. Mario Rizzo presents a more nuanced version of Keynes with respect to fiscal stimulus.
2. The Money Illusion — an interesting new blog from Scott Sumner. I would note that his posts on the current crisis and the refutation of the Austrian business cycle theory by Friedman and Schwartz are particularly interesting (I happen to disagree with his conclusions, but they are interesting nonetheless).
3. The Theory of Money by Jurg Niehans — a classic.
4. Great Depressions of the Twentieth Century edited by Kehoe and Prescott.