I have been riveted by the Facebook status updates of Japan Earthquake Animal Rescue and Support (JEARS), whose volunteers are trying to help the many animals left behind following the earthquake and tsunami in Japan. Some of the animals are homeless or abandoned because their owners are now dead. Some are in this situation because their owners are not allowed to have them wherever they are living now. The stories of animals reunited with their families brings a tear every time. If you speak Japanese and can be entirely self-funded (taking care of your transportation and food and at least some accommodation), you would be welcomed onsite to help with JEARS. Otherwise, the best way you can help is with a financial donation.
JEARS is one of those organizations that gets Facebook, that understands you have to publish regularly with updates that help people understand you are doing great work — not just endless posts about the donations you need or something you are selling.
And on that note: animal shelters in tornado-stricken areas of the USA are facing dire straights. They need money, they need food donations (and donors need to bring it onsite to them – they CANNOT come get it), they need donations of washing machines, they need bedding, and they need people to adopt or foster abandoned dogs and cats. The shelters serving these areas are easy to find on Google.