Most of the people in the world don't have access to the banking system. If they have a good idea, but lack financing, they cannot just go to a local bank to ask for a loan. Their only option are rich relatives (if they have any) or local moneylenders. In both cases, they are charged such high interests that they must be very lucky in their endeavor to be able to successfully pay back the loan. It was Muhammad Yunus and Grameen Bank who first addressed this issue, but only through the power of Internet we, the rich people of the west, got to see first hand how much of a difference a small loan can make in people's lives. I've got introduced to the world of microfinancing thru Kiva of which I'm part for the past two years. I've only invested $50 but since everybody fully repaid her loan, I was able to fund 6 loans with this money.
I very much recommend you to try Kiva yourself. Choosing which loan to support gives you a very special introspection in the lives of people in faraway places with very different problems than we have.
So click here now and empower somebody's life!