For me: community gardening, food sharing program, esperanto speaking group, nonfiction book club, occasional board gaming. Used to volunteer with a fix your own bike sessions.
Though I think I'd like to discover more hackspaces soon.
For searching in your local area meetup.com might be useful, it has for me.
But obviously it is different for what your interests are. Contributing to online communities counts too!
What interests do you think you'd like to share/learn with others?