Last year Lauren Faust ran a charity auction, putting up development sketches from MLP:FIM on ebay with the proceeds to benefit survivors of the disaster in Japan. Well, she's running another charity auction starting on Friday to benefit a storyboard artist and his family dealing with serious illness in their children. You can find more information about this here.
Operation Sharing Kindness is a long-time brony movement that has been raising money for the organizations Toys for Tots (toys for needy children) and Doctors Without Borders (international humanitarian aid). I definitely hope you'll give them a look and a donation: you can read up on Operation Sharing Kindness here.