Although technically, this is a whole "system" of litter box, I consider it of prominent enough attention to include it with cat litters. We have personally been using two Breeze Litter Systems for well over a year, in addition to three regular litter boxes, with World's Best.
Breeze utilized a unique system, in that the urine filters through the pellets into a separate pad-lined tray in a compartment under the box. As long as the solid waste is regularly scooped, and the pad in the tray is changed regularly, there is virtually no odor. The latter is the key. Although some users report only having to change the pad every six days or longer, my cats generate a lot of pee, and four days is about the maximum.
Except for its price, World's Best Cat Litter live up to its name. Except for occasional testing purposes, I have used no other litter for years, and my cats love it. Made of whole kernel corn, this litter is virtually dust-free, and clumps exceedingly well, so it can be safely used in automatic litter boxes
The clumps do not stick to the bottom and sides of the box, which is a complaint often voiced about other litters. The natural corn odor is mild and unobjectionable. Regular scooping keeps the box relatively odor-free, so that the box doesn't need to be completely changed out often, mitigating the initial costs.
A potential downside is the possibility of aflatoxin fungus. Please read my review for more information and cautions.
Feline Pine is made of natural pine pellets, and is dust free (a boon to asthmatics and their cats), non-tracking, and flushable. It's economical too, as the litter only needs changing when the pellets have dissolved - about every two weeks, on average. Feline Pine is non-clumpable, and some cats may find the pellets uncomfortable on their feet.
ConsumerSearch.com ranks Feline Pine the Best Biodegradable Litter. I personally would question the practice of flushing used Feline Pine down the toilet.
The added fillip, one which will be attractive to cat owners with cats susceptible to lower urinary tract disorders, is the addition of a special pH indicator which causes the litter to turn pinkish incrementally when the urine pH rises - the brighter the pink, the more serious the problem.
When I tested the product one of my cats was suspected of having FLUTD. be sure to read my review to see the results of my test of this product.
Sometimes for one reason or another, cats begin to avoid the use of their litter box, or a previously outdoor cat needs to be trained to the use of a litter box. Cat Attract was developed by a feline-only veterinarian as a "training litter." This litter contains a natural herb "attractant" that piques a cat's curiosity in the litter.
Although it is a clumping clay litter, it has been found to be very useful in retraining cats to the litter box. I would use it temporarily for that purpose.
Read ConsumerSearch.com's analysis of Dr. Elsey's Cat Attract Litter.
The advantage of Tidy Cat Antimicrobial litter is that it contains an antimicrobial agent for controlling odor-causing bacteria, a plus especially for small households.
My review is pending.
Fresh Air Cat Litter was first marketed in the fall of 2012, and I tested it for review in September. It falls under the classification of specialty litters, as its manufacturer, ThePetLoo.com markets the litter system as being superior to other premium cat litters for odor control, by a specially designed carbon pad (litter box liner) designed to neutralize the ammonia odor.
I tested two versions of the litter over a period of three weeks in September, 2012, and my review is based on the second version.