I opted not to give Lady her rabies booster this Spring when it was due. She is twelve and immune compromised due to her diabetes. She got very, very sick when she had her last booster three year ago. She had to be on steroids for a week and her blood sugar was sky high which can lead to a life threatening diabetes complication called ketoacidosis.
The rabies shot can be very dangerous. Read this:
http://dogs4dogs.com/JR_Articles/Rabies.html
Some states allow the vaccine to be waived with a vet's certificate. I live in North Carolina which doesn't have that option. Lady doesn't go outside anymore so I am not worried about it. She has had the booster all her life so I am sure she is still protected.