I don't know about sharing photos, but the idea of a back-up storage seems to be a good one. It looked to me that everyone thinks they have the most beautiful dog, cat, or child.

http://www.flickr.com/photos/schonafrye/
http://www.flickr.com/photos/81013471@N00/
http://www.flickr.com/photos/8361428@N06/