Changing the world

I really like how sometimes a small change, or a new technology meant to solve one problem, can end up making a huge difference in other ways.

For example, a service called M-PESA allows people in Africa to pay each other via text messages on their cell phones. Households using M-PESA in Kenya have increased their incomes by 5-30%! How? They are using the phone account as a bank account. It enables them to have emergency savings which means when something goes wrong they don't have to sell the cow or their livelihood. From the Economist:

the service is used by some people as a savings account. Having even a small cushion of savings to fall back on allows people to deal with unexpected expenses, such as medical treatment, without having to sell a cow or take a child out of school. Mobile banking is safer than storing wealth in the form of cattle (which can become diseased and die), gold (which can be stolen), in neighbourhood savings schemes (which may be fraudulent) or by stuffing banknotes into a mattress.

Do you have a similar story about how technology or free software has improved life in a developing country in unexpected ways?