As applications for the 2011 Inc. 500|5000 arrive, we thought it would be worthwhile to shine a spotlight on some of the companies that are vying to appear on our ranking of the fastest-growing private companies in the U.S. (For more information and to apply, go to One that caught our eye was Austin-based SPIbelt, a company that makes small personal item (SPI) belts for outdoor and indoor activities and travel.

Kim Overton can be classified as a serial entrepreneur. In the mid-90s she co-founded a tech company with her friend. After that she helped The Lord Group advertising agency develop its interactive division. And most recently, she invented the SPIbelt (pronounced spy belt) in 2006.

"I was out on a run and I had my key tucked into my bra top and I thought 'man, this is uncomfortable. I just need a simple belt.' After that run I went and bought the stuff to make the very first belt," Overton says.

The goal was to make a small, convenient pocket that would fit all of your essentials while you are working out: keys, ID, cell phone, inhaler, etc. Overton started wearing her SPIbelt to the gym and got positive feedback from clients. She began sewing together the first batch of belts from her house and targeting members of the running community to increase interest in her product. Soon she quit her job so she could devote all of her attention to her new company. She recruited her brother Volma to become the national brand ambassador and help spread the word.

"One customer led to another and one store led to another and it just started booming," she says. "A lot of people started hearing about us from being at events and the reviews were just phenomenal."

Since its launch, SPIbelt has added 10 employees and revenue has grown from $150,000 in 2007 to $7 million in 2010. Overton has already expanded into Asia, Australia, Canada, and Europe, and has plans to enter other countries.