If you own one or more birds, ferrets, guinea pigs, hamsters, or rabbits, you are probably already aware of the problems with your pet and clumping clay kitty litters (especially ferrets!). And, you are probably searching for a good alternative.
Bird owners! What works for cats does not always work for birds, and can in fact be fatal. Please see this veterinarian's article for more information.
For more information on guinea pigs, see the definitive piggie site, Guinea Pigs Online.
Rabbit owners: Please visit the House Rabbit Society's Web site for a discussion of alternatives to clay litters for rabbits.
Please don't use any scented shavings (including pine and cedar). They contain aromatic hydrocarbons that can cause respiratory problems; they are also suspected of causing permanent liver damage. Use only dust-free litters. (One ferret owner who wrote to me uses CareFresh, which she loves.)
For more information on pine bedding, see http://www.cavycages.com/pine.htm.
For information on the definite problems with some woods, with a list of some alternatives you can use, see http://www.rabbit.org/journal/1/liver-disease.html.