With years of experimentation I have found PineFresh from Cansorb Industries Inc. of Cleveland NC to be the absolute best litter for ferrets. It does not seem to have the problem of the aromatic cedar or pine shavings (litter box is hopefully not used as much for sleeping) This litter is compressed pine saw dust that absorbs many times more ammonia odors than anything else I've ever used. My only real problems are that it is by pound more expensive than other types but it seems to make up that cost in longevity in the box. It is not available at all grocery stores in this area either - Safeway and Weiss markets but not the dominant Giant stores. Litter Green may be fine for cats but seems to be particularly bad for ferrets. Clay is too dusty and seems to cause sneezing and even an infection in my ferrets. Never tried clumping litters and have been warned off of them but I forget the reason. I also use ground corn cob litter (available at feed stores). It is very clean and dust free but does not absorb odors. I use it with my kits as I want to avoid any possible effects of the pine aromas on the little ones. I also change their litter every day to avoid infections. This litter does not absorb odors very well at all but is the least dusty of anything I've tried. I'm trying a recycled paper product but haven't formed any opinion at all yet. I've had ferrets for six years now and currently have far more ferrets than I ever expected to so I use quite a bit of ferret litter. Hopefully I won't become known as the fetter litter expert around here. Not very glamorous title huh? bill killian zen and the art of ferrets [Posted in FML issue 0859]