Ever had a great business idea? Maybe you've had one of those eureka moments and thought: now that would make some money. These entrepreneurs certainly did, and though their businesses started small, they became big moneymakers. Here's a list of seven ideas that made their owners successful entrepreneurs by accident.

In Pictures: Consumer Fads That Haven't Faded

  1. Geox
    Mario Moretti Polegato was taking a walk during a business trip to Reno, Nevada, when he was bothered by how uncomfortably sweaty his feet got. To solve the problem, he punctured his rubber-soled shoes - and the idea for Geox's breathable shoes was born. Polegato patented the idea. He continued to develop the idea within his family's small footwear company into the internationally known company it is today.
  2. Mancakes
    It's an all too-familiar story: David Arrick, a lawyer, was laid off in 2008. He tried in vain to get a job, and quickly found himself cooking at home to save money - including cupcakes. Frustrated by the pink and girly aesthetic of cupcakes, Arrick invented the manly cupcake with Mancakes, his online cupcake delivery business. He maxed out his credit cards and pulled money from his 401(k) to start Mancakes, which has since grown so fast, he's hoping to expand to different cities soon.
  3. Momzelle
    When Christine Poirier was nursing her newborn daughter, she found that her clothing just wasn't designed for the job. To solve this practical problem, she designed a nursing top. Finding that her friends and midwife were interested in her nursing wear, she partnered with her brother Vincent to create Momzelle, a business specializing in nursing wear. Momzelle has grown from Poirier's eureka idea into an online and retail business that continues to grow. (Find out if you have what it takes; read Are You An Entrepreneur?)
  4. Joseph's Lite Cookies
    Joseph Semprevivo was a 12 year-old diabetic when he concocted sugar-free ice cream in his parents' restaurant kitchen. Customers loved the ice cream, and with help of his father, they expanded the business to oatmeal cookies and other products like peanut butter. The success of the cookies led the Semprevivo's to abandon ice cream to focus solely on cookies. Catering not just to diabetic but also to health-conscious consumers, Joseph's Lite Cookies is now a multi million-dollar business, serving 42 countries and approximately 140,000 U.S. stores.
  5. Stroller Strides
    After the birth of her child in 2001, Lisa Druxman faced a problem many mothers face: how to work part-time and still spend time with her child. A former fitness instructor, Druxman started Stroller Rides, an exercise program where moms use their strollers to get exercise, speed walking and toning as they stroll. The idea took off, and Stroller Rides now has over 300 franchised locations across the country. Lisa has also written a book on her business success titled "Lean Mommy: Bond With Your Baby and Get Fit with the Stroller Strides Program."
  6. Vocation Vacations
    Ever wanted to try out a new career without committing to the job first? Brian Kurth did, and while he was stuck in traffic, he pondered the idea of vacations designed to let you try out a new profession. Kurth was a laid-off dotcom professional who started Vocation Vacations in 2004 with an idea and 10 mentors in different dream jobs to host his clients. The business has since grown to more than 130 mentors, and is now a full-time job for Kurth - and it all started with an idea while sitting in traffic.
  7. Sassybax
    Amanda Horan Kennedy had a simple shopping wish: she wanted a bra that she could wear under her cashmere sweater without it showing. She looked everywhere, even at high-end department stores, but none of the bras she found made her cut. So she had an idea: she cut up a pair of pantyhose into a make-shift bra and ... it worked! She scraped together enough money and called in favors to develop the off-the-cuff prototype into Sassybax, which is now a full-time business for Horan Kennedy, catering to boutique and high-end stores like Neiman Marcus. And it all started with a shopping trip. (Read more stories like this in Ridiculous Ideas That Made People Millions.)

The Bottom Line
Tough job markets like the one we're facing now are a breeding ground for start-up businesses just like these. Are you inspired? Think of ways you can meet a need that isn't met today - that's how most of these successful businesses started out. Many of the entrepreneurs you've read about turned necessity into innovation, so look for opportunities around you where you're thinking: if only there was a better way to …

Make sure you patent your idea, and contact your local small business center for help in starting your business off right. With a great idea and a lot of perseverance, you can become your own success story. (For more on the importance of patents, read Patents Are Assets, So Learn How To Value Them.)

Catch up on what's making news this week. Check out Water Cooler Finance: Bailouts, Buffett-Rock And Prison Brawls.

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