Kiva to the left, Kiva to the right!
Right now Kiva is offering a free $25 loan to get you started if you sign up through this link they sent me.
It's a totally free way to try it out and see how micro-financing works... you can see all the loans I've participated in here. (the latest one being Ha, a seamstress in Ho Chi Minh City, Viet Nam)
Jonah and Benjamin have each made a loan, although they cannot even believe how long it's going to take for the people to pay it back! (anywhere from a few months to over a year)