I donate 10% to Freedom Service Dogs of America.
From the website: "Freedom Service Dogs is a nonprofit organization that enhances the lives of people with disabilities by rescuing dogs and custom training them for individual client needs. Clients include children, veterans and active duty soldiers, and other adults. Their disabilities include Autism, Traumatic Brain Injury, Cerebral Palsy, Spinal Cord Injuries, Muscular Dystrophy, Multiple Sclerosis, and Post Traumatic Stress Disorder (PTSD)."
This organization's mission hits close to home because my own daughter is diabetic and some dogs can be trained to sense impending seizures or insulin reactions.
I don't know if it attracts any clients, but that's not why I did it. Rover is not my primary source of income, and my belief is that it is important to help as many others as I can, in any way that I am able. If nothing else, it should help in the karma department. :-)