An alternative bank: Grameen

Is it possible for a bank to thrive by lending to people without collateral? Professor Muhammad Yunus believed that it was. Now his Grameen Bank is paying off and, apparently, lifting multitudes out of poverty. Might this be a model from which Christians can learn and apply elsewhere? Might the proliferation of such banks help to ameliorate, if not altogether solve, the problem of global poverty? It would seem to be worth looking into.