Comment Check your local community first (Score 3, Informative) 112
I'm guessing that your local community probably has some needs for your skills, whether its an elementary school, charity organization, adult education program, etc....You'd be surprised how many people are held back by their lack of basic computer skills Slashdotters think they were born with.
I share your same desire to be able to donate my skills to humanitarian organizations in need (I can't build a house with my hands, but I can sure set up networks, workstations, infrastructure, etc), but many people in the world need basic services like toilets a lot more than they need electronics.