I was going to make the traditional list of "things I am thankful for", derp derp, but that would be a very long post, including such things as clean water, pugs, and Canada.
Instead, here is a list of groups whose hard work I am thankful for.

11/19/09: Wilma, rescued by the ASPCA
The first and oldest humane organization in the Western Hemisphere, the ASPCA works to rescue animals from abuse, pass humane laws, and share resources with shelters nationwide. 
The United Nations Children's Fund was created by the United Nations General Assembly on December 11, 1946, to provide emergency food and health care to children in countries that had been devastated by World War II. It has since evolved into the world's largest advocate for children in impoverished and war-torn nations, providing long-term humanitarian assistance to children and their mothers.

Founded as Point Reyes Bird Observatory in 1965, PRBO Conservation Science is dedicated to conserving birds, other wildlife and ecosystems worldwide through innovative scientific research and outreach.
If there's another cause you favor, you can always find a charity of your own to support. :D
Or if you've got a few minutes, you can donate your clicks to a good cause.
Happy Thanksgiving, 感謝祭おめでとうございます。:3