Humane Chain site, you really must check it out and join in. My partner and I have contributed our image to it, and so far, there are over 6000 photos on there!
The site is run by WSPA, a worthy global organization. Check out their website to see all the good work they have been doing for over 25 years.
And while you are at it, check out their merchandise via Neo Tokyo, whereby 20% of profit will go to the World Society for the Protection of Animals (WSPA) to aid in their many campaigns.