Who was that fat cat we pictured yesterday?

That's Hercules, who a year ago was just another overweight feline.

Today, in addition to becoming an Internet sensation, he's being featured in an article about pet weight loss in Martha Stewart Living, and may become spokeskitten for a low-calorie cat food.

It all started when he ran away. His owner, Geoff Earnest, 31, who has cystic fibrosis, went to the hospital for a double lung transplant. Despite having a cat sitter, Hercules broke out.

Earnest survived his surgery, returned home, grieved over the loss of his cat, who he assumed was dead, and went on with life -- until one night he saw his cat on TV.

The cat had been brought into the Oregon Humane Society after a family found him stuck in a doggie door leading outside from their garage. It seems Hercules had been sneaking in through the doggie door and chowing down on pet food -- until the day came he was too fat to make his escape.

The Humane Society called the papers and TV stations to tell them the story of the fat cat.

Hercules -- who was called Goliath while in the shelter -- ended up in the newspapers, on TV and on YouTube, all 20 pounds of him. He has gained lots of fame, and lost only a little weight. Earnest says he walks Hercules for exercise every morning and the cat now tips the scales at 19.5 pounds.