Bill Gates has been pushing to help eliminate Polio world wide, you can check the Bill and Melinda Gates foundation web site and see it there is anything you can do to help that effort.
Maybe organize a local fundraiser or something. Its not specifically programming related but it will definitely help people in poor countries! Or how about a hack-a-thon fundraiser?
And for the record I have been a Linux geek since about 1994, so not a Microsoft fan. But I am a fan of good public health policy, so for this I will give Bill a big round of applause.