Obtaining Grants for Open Source Projects?

Michael Chisari asks: "Does anybody have any leads or information about where and how to apply for grants for open source projects? I've been working on an open source social networking software called Appleseed for around two years now. The goal is to be a free, distributed alternative to MySpace or Friendster where users on separate Appleseed websites can fully interact with each other. The project is huge, and while relatively far along, I've had a hard time keeping up while maintaining the full time job necessary to pay the bills. Ideally, I'd like to get funding so that I could focus exclusively on development. I'd prefer a grant from a foundation as opposed to corporate funding. Individual donations are nice but can't always be counted on. I'm not sure where to find organizations which provide grants for free software or social networking."