Do something.org puts out a yearly list with its pick for top do-gooders, aka celebrity-type that went above and beyond the call and made an impact.
Here is this years list. There are some obvious picks, george Takei comes to mind with all his work in the LGBT community, but other names are surprising, including the top pick.
Olivia Munn does work raising awareness of fur farms with PETA. She also kicked off Do SOmething.org's Green Your School campaign.