Marco asks why I want to nationalise the banks.
If you are the absolute ruler of a country, then it will often be easier to let your subjects starve then to take more difficult action to solve a problem. They're subject to you, after all. If you are a democratically elected leader, you do not have the luxury of letting your constituents starve. This is why the last serious famine in India was in 1945.
If you are a business, customers that you can make money out of are in the position of constituents; customers who will only ever cost you money are in the position of subjects. Human nature being what it is, you will suck up to the first, and treat the others with the minimum amount of consideration you can get away with.
Generally speaking, any service that absolutely everyone needs to consume should therefore be provided by an organisation into which everyone has input- i.e., the public sector. Privately-owned banks will always have an innate tendency to piss on the poor, as long as these uneconomic customers are foisted on them. If everyone had the option of taking their wages or government benefits as cash, and opting out of the banking system, then by all means let it be private. But if people are going to be forced to participate, for the love of God let them participate as constituents, not subjects.