Everyone needs love...even animals. Many pet shelters will let you play with the animals if you call ahead and arrange a time. This is a great rainy day activity. Another great idea is sponsoring an animal and helping them find a home by posting signs in your neighborhood.
We like Brooklyn Animal Resource Coalition (BARC) www.barcshelter.org which is a not-for-profit, no kill, privately run animal shelter that provides a safe haven for abandoned animals and works to find them permanent loving homes. They also have a volunteer schedule on their website to make it easy to help out.
Happy Giving!