Necessity is the mother of invention, the saying goes, but Edmonds resident Melinda Knight believes that clever inventions are often created by mothers looking for solutions — such as a tiny brush designed to clean Sippy Cup straws.

That invention, plus creations like travel-ready bed sheets for those who are a little squeamish about hotel room linens and portable ballet flats for days when you simply have to kick off your high heels, can be found on Knight’s recently launched website, www.womentorz.com.

“It’s basically an eBay for women inventors,” Knight said. The online marketplace is designed to showcase inventions made by women for women, with unique offerings that can’t be found in stores. And nearly all of those women happen to be mothers, she said.

Knight, who lives in Edmonds with her husband and two small children, said it was her own disappointing experience that inspired her to create Womentorz. After hearing about a national casting call for women inventors during a “Live with Kelly and Regis” show, Knight rushed to put the finishing touches on her own invention — a tray designed to hold a laptop and be attached to a recumbent bicycle. She flew to Chicago with her prototype safely tucked in her husband’s golf bag, only to discover that competition was more about finding a TV personality than a good invention.

There was a silver lining, however. Knight came home with contact information for many of the thousands of other women across the U.S. who weren’t selected as finalists in the competition, and were now unsure how to get their products to market. She began thinking about a way she could unite those women with the common goal of marketing their inventions, and Womentorz was born.

One of the connections that Knight made in Chicago, Jennifer Cannon, ended up becoming Knight’s business partner and handles communications for the company. Knight and Cannon started a blog and invited women to talk about their various inventions, and also shared their idea for a website devoted to their creations.

Womentorz, which launched on Nov. 1, currently has 22 businesses selling products online. Sellers pay $40 per month for the first product listed, plus $10 a month for each additional item. Participants get a web page for their business that highlights their product and allows buyers to purchase directly from the site, plus nationwide public relations and marketing support for their inventions. In addition to the monthly fee, Womentorz collects a 5 percent commission on each sale.

For now, Knight is working 20-hour days maintaining and promoting Womentorz as well as three other businesses that she and her husband own —  plus raising a family. She has relied heavily on social media like Facebook and Twitter to spread the word, and on Friday night Womentorz participated in a Twitter Launch Party — essentially an hour-long event where people visited the site, browsed products and tweeted about their favorites. The site not only received 2,000 visitors during that one hour, Womentorz was the number-eight “trending topic,” due to more than 3,500 tweets sent about the site during the evening.

“Womentorz is quickly becoming a destination for women inventors to get their product to market and shoppers to find unique purchases,” Knight wrote in a blog post Saturday morning. “You can literally feel the buzz, it’s so strong. Big things are in store for the month of December.”

To browse any of the products on Womentorz, visit the site and click on the “Shop Inventions” link.