Sinsull, I said anything I DON'T already have......I have (currently) 4 cats, 4 Corgis (dogs), 1 possum, 1 son, 1 daughter (that seems like 4) and 1 husband. I don't need no damn litter of anything!! (grin) Rocks are fine--they don't need food, clean clothes or clean litter boxes.....