As individuals, we can collectively do a lot of good by donating money where it does real good (fighting corporate interests, feeding the hungry, and donating to worthwhile IT projects). I just invested (yes, I consider this an investment!) by making small donations to the FSF, Debian, and Ubuntu Free Software projects.
BTW, I have a friend who lives for charitable work - several years ago, he gave me some great advice on which charities to avoid (or contribute to) based on how much money they spend in administration costs. I have monthly donations taken out of my credit card for the American Friends Service Committee, Habitat for Humanity, and the Heifer Project - all recommened!! Also, if you make monthly contributions to a charity, make sure that you call them up and have them *not* send you information and requests for more money in the mail - that is administrative overhead - ask, and they will just quietly take your money and not waste it on mailings back to you.