April 14, 2002 -- When you live with animals, mandatory waste management comes with the territory.
For cats, that means a litter box that requires daily scooping, and for dogs, regular walks.
But two new inventions are putting innovative, convenient spins on pet waste cleanup.
Consider the Litter Free Self-Washing Cat Box. This appliance, which sells for $299.99 at Petco stores, looks like an ordinary litter box but is actually a high-tech comfort station that collects your cat's waste while relieving you of scooping duty.
Call it a cross between a toilet and a washer-dryer.
Here's how it works: Hook the Litter Free device up to an incoming water line and an exit line, then plug it into an electrical outlet. Instead of old-fashioned kitty litter, the Litter Free comes with dust-free "training granules" made of an environmentally safe plastic compound.
Simply push a button, and the appliance circulates water, mixed with a non-toxic blue cleaning solution, through the granules, flushing the soiled water down the drain.
Then it dries the granules with a hot air blower, so the box is ready for your cat's next visit.
The whole process takes less than half an hour. You can even pre-set the timer so the Litter Free flushes itself while you're away.
As every cat lover knows, felines are just as finicky about loo arrangements as they are about food, and many won't hesitate to reject newfangled litter options.
Rosemary Joyce ought to know: She lives with four rescued cats. But, she's happy to report, her quartet warmed up to the Litter Free with no protests.
"It took them about a week to accept it," she said.
Joyce enthusiastically calls Litter Free "the cat box of the 21st century." She happens to be a publicist, and was so impressed with the product that her firm, Manhattan-based TJ Public Relations, took Litter Free on as a client.
However, for those whose pets may not take to the cat box of the future, Litter Free offers a 30-day trial period. If things don't work out, the company will refund your money.
Unlike cats, dogs aren't accustomed to evacuating in a box, which is why they must be taken on regular walks outdoors.
But now, for the convenience of apartment-dwelling dog lovers lucky enough to have access to a balcony or terrace, there's a viable box option: Nelson's Backyard, an ingenious wooden planter filled with every canine's favorite "litter," grass.
The backyard-in-a-box is the brainchild of Audra Winston, who shares her Fort Lauderdale, Fla., high-rise condo with a Cairn terrier named Nelson.
The box is made of cedar, which weathers nicely with exposure to the elements, turning silvery-gray in color.
It's fitted with a plastic liner and filled with St. Augustine cultivar, a hardy species of sod.
And it comes in three sizes: small (20 x 28 x 6 inches), medium (38 x 28 x 6 inches) and large (38 x 56 x 6 inches).
For giant breeds or multi-dog households, Winston advises buying two medium-size boxes and putting them together.
Prices range from $125 to $380, and refills and replacement liners are also available (to order, call  241-8146).
Nelson's Backyard is certainly attractive enough to look right at home on the most style-conscious outdoor aeries of Manhattan and Miami Beach. But how does it smell?
"The dog's urine is eaten up by the microbial action of the soil, leaving the grass clean and odorless," Winston claimed.
Of course, it's up to you to be good about removing your pooch's solid waste with a plastic baggie, and to keep the sod watered and clipped, just like any well-tended lawn.
The self-cleaning grass of the future has yet to be invented