My favorite charity for this type of giving is Bread for a Hungry World:
http://www.givebread.org/Their goal is "Breaking the cycle of poverty", and they do it by things like microloans, goats and chickens. They also provide milk and school supplies for children in Honduras.
Please note that this is a faith-based organization, but the people helped are not required to be members of any church, or express any type of religious faith.
One of the main reasons I like this outreach is because the overhead is so low. They have one full-time director, and an administrative assistant who also works for three other ministries. They have office space in a building owned by our church, and all of their salaries and expenses are paid by the church contributions. This means that 100% of contributions that come from outside the church go directly to helping people.
My daughter is one of a group of 20 who are going to Honduras next month to work with our people there. She will spend her 18th birthday there. We were a little upset with her being away on such an important day, but how do you argue with a girl who thinks it's wonderful that she will become a legal adult in a foreign country, helping people who need help desperately. (And if you want to see how desperate they are, watch the video on the Dump in Honduras. This is where they are going.
http://www.vimeo.com/14121449 ) I'm so very proud of my girl!