What about a Asus U36? See e.g. the U36SD-RX145V model or the U36SD-RX117X model.

The display is not as good and the touchpad is probably inferior, otherwise it looks like a good fit for $$$ when compared to the Macbook Air.

There's Random Hacks of Kindness (http://www.rhok.org/):

"Random Hacks of Kindness is a community of innovation focused on developing practical open source solutions to disaster risk management and climate change adaptation challenges. Random Hacks of Kindness was founded in 2009 in partnership between Google, Microsoft, Yahoo!, NASA and the World Bank."

Johnny Long founded Hackers for Charity in 2008: http://www.hackersforcharity.org/ - see announcement talk: http://www.youtube.com/watch?v=5CWrzVJYLWw

Hack for Change (http://hackforchange.com/) might be interesting as well.