"We were one of the first in our industry to offer prepaid phone service and continue to see an opportunity to provide customers with easy and accessible wireless service, which is why we've looked to T-Mobile to expand our prepaid handset offerings, " said Jesus Delgado-Jenkins, 7-Eleven's senior vice president of merchandising, marketing and logistics.

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The company's Boost Mobile division, which markets prepaid cellular phone service to young consumers using sports- and music-oriented marketing, has seen excellent growth this year.

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Prepaid mobile phone service is more common in Europe and the rest of the world than it is in the United States, and Euronet provides airtime PINs for more than 100 national and regional networks.

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It offered subsidized handsets and prepaid phone cards, and cell service grew from 9 million subscribers in 2000 to 39 million today.

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New ways of dealing with micro-payments are emerging, such as by deduction from a prepaid account with a computer company, Internet-service provider or mobile-phone company.

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The sector is also seeing controversy as Virgin Mobile engages MetroPCS in a legal tussle over Metro's MetroFlash service, which lets consumers buy prepaid minutes and put them on any phone, even ones sold by rival companies.

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