United Animal Nations (
www.uan.org) is a great organization worthy of support.
I would give $500 to UAN's Lifeline Grants program; it helps pay emergency veterinary bills for people who can't afford them. Hopefully the recipients would "pay it forward" when they were able to.
With the remaining $500, I would pay the travel expenses for low-income volunteers to travel to UAN's EARS (Emergency Animal Rescue Service) training sessions. EARS volunteers go in and rescue animals who need rescuing, for example during natural disasters like Hurricane Katrina. With their training, those volunteers should be able to go on helping animals long in to the future.
Oh, wouldn't that feel good?