Melinda Gates set the microfinance world ablaze last week when she announced the Gates Foundation's five-year, $500 million Global Savings Fund. It was welcome good news for microfinance after a rough few weeks following the Andhra Pradesh crackdown

Gates noted that "the poor can and do save  ... (but) they want to do it safely and efficiently." She went on to acknowledge the success of M-PESA across Kenya. Yet the middle ground between M-PESA customers and the poor "(burying) their cash in a hole in the ground or (hiding) it under the mattress," actually contains a great diversity of more sophisticated informal financial tools for saving.