There are far better free software projects to donate to. Diaspora raised more than 200k last year to write a simple web application, it's still not finished... and they need more?
Both http://opensource.appleseedproject.org/ and https://n-1.cc/ (elgg) are projects made on much small budgets and teams (appleseed is one guy AFAIK), and they're far better. Your money won't be efficiently used if donated to Diaspora.
I would pick some piece of free software you use often or you think Linux needs, and donate to that TBH the diaspora guys come off clueless when you watch their initial fund-raising video. The software itself is pretty bad and requires all these esoteric dependencies rather than using tried and tested libraries.
Video: http://www.youtube.com/watch?v=oqxQgfQD24M
Wow genjix you just crushed our dreams lol