The line between volunteer work and charitable missions or charitable giving blurs sometimes, and my answer depends on where that line is drawn. I think I fall toward the latter end of the spectrum in my outreach, as detailed in my thread on it, which may be of interest to those posting here (though it's more focused on monetary giving, so the scope is slightly different).
I'm still newish in my city, so I may look into what's out there. I honestly don't know, despite being active regularly in more passive charity events. I'm also part of a large networking and social group, which partners with a lot of volunteer organizations, so I know they're out there; just not the details. Thanks for pointing out this gap in my knowledge, though haermm
Sin, you mentioned creating your own. What would be its purpose and structure?