A Post-Capitalist Future is Possible by Doug Henwood.

The Revenge of Karl Marx by Hitchens.

I caught Obama's point man on the economy (or "political economy"* as Marx, Hitchens and probably Henwood would say) Larry Summers on Charlie Rose and when Rose asked him which economist or thinker is most relevant to understanding the crisis, Summers didn't hesitate to respond with "Keynes."

But Keynesian economics took a hit in the late 1970s when welfare states and relatively strong unions came up against high inflation. Central Banks raised interest rates to unprecedented high level and brought on a crash, which tamed inflation but the Right took advantage and won the political battle. (There was stagflation thought to be caused by Nixon's wage and price controls which were followed by cost-push shocks in commodities and the oil crisis of '73 which was a result of another Arab-Israeli war and OPEC's limiting of supply.)

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*The main political question now is to what extent the administration will take on the banking/financial institution lobby - as former IMFer Simon Johnson among others has been pointing out - and demand "clawbacks" and recompense for the taxpayer. There's also the question of the future regulatory environment.