This organization is doing good work in Haiti, check it out: http://mohhaiti.org/

They get a stellar rating; to my recollection, 96% of donated funds go to the cause (4% overhead).

They're an overtly Christian organization, which may or may not be your thing. But they're doing good work.

Disclaimer: A company I worked for did some work for them a couple of years ago. I'm no longer affiliated in any way.