Previous posts have examined how private enterprise can fight poverty through "creative capitalism" and corporate social responsibility. But one old idea made the rounds this week, albeit with a new spin: helping the poor by taxing global financial transactions.

The plan, proposed by Stephan Schulmeister of Austria's Institute of Economic Research, would tax global financial transactions — such as stock trades — at a rate of around one-hundredth of a percentage point. Even at this miniscule rate, Schulmeister estimates that such a global micro-tax could bring in revenue of up to $230 billion a year. Theoretically, this money would be used to finance development aid and projects aimed at helping the poorest cope with problems like climate change and rising food prices.

But the idea is not without its critics. Research from the World Bank notes that while the basic philosophy behind such taxes is economically sound, determining how to redistribute the revenue is likely to be politically problematic. An essay on the Organisation for Economic Cooperation and Development's website also wonders whether micro-taxes are administratively feasible or whether political leaders would actually use the tax revenue for development.