I'm not sure if this one is geographically convenient for you, and I'm not sure how big the people component is for it, but I know CERT volunteering can keep you pretty occupied.
I'm really looking for something either important to me or something I can teach to others based on my experience. Short of a full biography of myself I don't think random people are going to just jump to satisfying opportunities. I'd like to teach or mentor, but my specialty would be art and coddling middle aged women into painting roses is the kind of art volunteer teaching that immediately springs to mind. And makes me want to vomit on middle aged women. I've also looked into domestic violence volunteer work despite the comment about vomiting on women. The most happy I've been teaching was showing guys at work how to use a table saw but volunteerism and a handsomely outfitted woodshop seem opposed to each other. I guess I'm saying I don't want to be busy as much as I want to do something I care about. Hubski may not be the place for me to find what I care about.
Maybe start contributing The Archive Team's efforts? There's a lot to learn there, and the things you learn will be useful later on in life.