The huge success of the iPod continues to generate strong sales for third-party firms, including XtremeMac.

An LA Times report looks at how the iPod ecosystem has given birth to an array of successful third-party companies. It examines and compares other industries which work in this way, including the car industry.

All such industries have one thing in common: they are driven by smaller operators "with big ideas", the report explains.

XtremeMac founder Gary Bart quit his job in December 2001. He designed and purchased 20,000 iPod cases, which he launched at Macworld Expo San Francisco in January 2002. He managed to get his first 4,000 case shipment in on the morning the show opened, the report explains.

"At the booth, customers were lining up four across and 30-40 deep," he said. "People were bringing in their iPods in socks, then buying a case and throwing the sock away." He sold all his stock.

Apple recognised early on that third-party developers are very important," said Bart, who sees a benefit in his company's relationship with the computer maker. "When the consumer looks and sees this world of support, it's very helpful."

The LA Times believes that the iPod is a perfect example of an industry evolution that favours small entrepreneurial start-ups.