Kiva

One of the most amazing ideas I've seen in a long time, Kiva is a microloan program for the world's poor. Basically, you choose to give $25 to someone to help fund their start-up business, and then you get repaid with interest. While there is some risk that the business will go under, Kiva says that fully funded loans (most loans are around $1500) have had 100% repayment since they began.

What a wonderful way to invest in humanity and help people to "pull themselves up by their bootstraps."