By Lisa Flam, CNBC.com
If you believe everything a pet owner could ever want or need has already been dreamed up, think again. Americans shell out more than $40 billion a year to make their beloved pets happy. And if they can't find just the right product to do the trick? Well, some entrepreneurial pet owners roll up their sleeves and create the product themselves. The result is a crop of small businesses that has sprung up around these products, and others that have expanded their offerings to meet pet-related interests. We asked the owners of innovative and quirky pet products about their inspiration, and the growing appeal of their products.
See the full slideshow: 11 Cutting-Edge Products for Your Pet
Price: $149.99 www.sureflap.com
Love thy neighbor? Sure. Love thy neighbor's cats sneaking into your home and causing a ruckus? Well, that's another story.
Nick Hill, a British physicist, was frustrated that neighborhood cats were entering through his cat door and fighting with his feline, Flipper, and eating Flipper's food. The break-ins left Flipper uneasy, said Hill.
Necessity is the mother of invention, and so Hill invented SureFlap, a cat door that only opens if it recognizes the microchip ID implanted in your cat. SureFlap can store the identities of up to 32 cats.
Based in Cambridge, England, SureFlap had global sales of $4.2 million last year, with U.S. sales making up 5 percent of that. But sales are increasing as word gets around. The door is popular among suburban pet owners, especially in California, Texas, Washington and Oregon, where pet owners also encounter other intruders.
"Common offenders in the U.S. are raccoons, but we have also heard of skunks, possums and even foxes coming into the house through regular cat doors," Hill said.
Treadmill TrainingTreadmill Training, Fitdog Sports Club
Price: Starts at $15 Place: Santa Monica, Calif. www.fitdogsportsclub.com
If walking on a treadmill can improve muscle strength, help prevent obesity and strengthen your cardiovascular system, why not have it do the same thing for your dog?
Working one-on-one with a handler, pooches at Fitdog Sports Club are trained to run or walk on the treadmill. The class has been growing since it began in September, with about 10 doggy clients so far.
Fitdog co-founder Andrea Servadio says the treadmill workout is a good option for owners short on time to exercise their dogs, for hyperactive dogs that need extra exercise, and for dogs with pent-up energy that can cause behavior problems.
The dog care facility was founded in 2010 by two former investment bankers who traded Wall Street for sunny California but couldn't find dog care they liked. "We built a day care that our dog would enjoy - so we knew many other dogs would enjoy it as well," says Servadio.
Price: Starts at $34.95 /www.pooppac.com/index.html (Also at Amazon and Wag.com)
Walking along the dog beach in Santa Barbara, Calif., Susan Davidson was disgusted by what she saw: People carrying plastic bags full of waste as they drank their morning coffee or stopped to chat with friends.
"It's absolutely gross and totally unhygienic," Davidson says. "I thought, there has to be a better way."
To keep the bag out of sight (and out of mind), she created the PoopPac, a rigid, zippered case with a charcoal filter in one compartment that holds used bags, another to hold small personal items, and a bag dispenser on the outside.
She's sold about 2,000 since she started her business in April 2010. It's one of those things that people don't know they need until they own it. And once they do? "People absolutely love it," said Davidson.
Soft ClawsSoft Claws
Price: Starts at $18.95
Soft Claws were invented by a veterinarian as an alternative to declawing cats. The vinyl nail caps, which are glued to a cat's nails to prevent them from doing damage from scratching, also add a little zing to the cat's look.
The caps come in 15 colors, including glitter and others themed to holidays like St. Patrick's Day and Mardi Gras.
The caps have grown increasingly popular in the 20 years that Smart Health of Phoenix has been their worldwide distributor. And sales are back up to pre-recession levels, due in large part to some communities, especially in California, outlawing the practice of declawing.
Controversy aside, the mostly female customers are loving the colorful caps.
"It's a fashion statement," said director of marketing Bruce Muller. "The new sparkle colors have been a big hit."
Price: $2 a pupcake in the bakery; $25 a dozen online www.icing-cupcakes.com
The cupcake craze has hit the four-legged set.
The three women who own Icing Cupcakes, who also happen to be dog owners, thought it would be fun to bake dog-friendly cupcakes to give away to customers who came in with their pooches.
Made with bananas, honey, eggs, whole wheat flour and topped with all-natural peanut butter icing and a dog treat, the pupcakes proved so popular that they're now a regular for-sale item, says co-owner Reyne Hirsch.
"For something we never planned to carry as a product for sale, we've watched our sales growing exponentially" since they came up with the idea in the summer of 2011 in their Katy, Texas-based shop.
Dog owners love being able to give their dog an all-natural treat, she says.
"It makes them smile the minute they see them," Hirsch says. "They can't believe something so pretty can be for a dog."
See the full list: 11 Cutting-Edge Products for Pet Owners
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By Lisa Flam, CNBC.com