Ask HN: volunteering/giving back?

I'm wondering what other HN folks are doing in terms of volunteering and giving back to the community at large, and how technology is affecting your choices? Generally, how do you approach the issue of helping the less fortunate?

Myself, for example:

* Made some microloans through kiva.org

* Looking into volunteering as a math tutor, found through volunteer-match.org

* Joined a "random acts of kindness" Meetup group