My favourite commercial with a cat in is the Bacardi Breezer one. That silver tabby is just so cute, I wonder how they trained it to dance? I heard somewhere that cat was in Stuart Little. He must be a feline celebrity!
I like the litter commercial for the Tidy Cats crystals, where the kittnes think they are diamonds, and the adult cats all like "thats not diamonds, that litter blah blah blah" and the kittens are like "WHATEVER!" They say it SOOOOOOO cute!