I've always thought that the most famous retired racing greyhound is Santa's Little Helper, the dog who was thrown out of the track and became a Simpson in the very first episode, Simpsons Roasting on an Open Fire. "He's a loser! He's pathetic!... He's a Simpson."
However, I think it's now safe to say that Bart Simpson is no longer the most famous retired racer adopter:
"Something magic happened in our kennels a few days ago. A very nice lady booked an appointment with us with a view to adopting a female Greyhound, to go with her male Jack Russell terrier Butch. We asked her all the usual questions including how long the dog would be left alone and she told us that she worked from home. Her husband and her lovely family and Butch were there. They finally found a little blue girl who got on great with Butch and it was love at first sight. One could see that they were a very kind family and their body language with the dog was marvellous. The family all agreed upon the little girl Sapphire and the lady completed the adoption form, signing her name, JK ROWLING. A very private but wonderful lady. We asked her if she would send us a picture for our website. She kindly agreed and here are some photos of a very happy Sapphire."
Welcome to the adopter's club, Ms. Rowling. I know Saphire is thrilled to have you and to be in her forever home.