NEW YORK (MainStreet) – Don’t you hate it when you come across a troop of Girl Scouts selling cookies and don’t have $4 in your pocket for a box of Thin Mints? Soon you may be able to pay with a credit card.

For a limited time, a few troops in the San Diego area will be accepting plastic for their cookies using a mobile payment device that attaches to the iPhone. The Mophie Marketplace device turns an iPhone into a mobile credit card scanner, allowing any vendor to accept credit card payments wherever they are. Cookie buyers will simply need to swipe their card and sign via the touch screen, and a receipt will be e-mailed to them.

A representative for Mophie told MainStreet that the devices were provided to the Girl Scout troops free of charge, as part of a pilot program to test a possible organization-wide rollout for next year’s cookie season. In a press release, the company said the program would also help the Girl Scouts learn about credit cards and give the scout leaders a chance to teach them about personal finance.

Mobile payment systems of this sort are perfect for small vendors who want take payments outside a traditional brick-and-mortar setting. It doesn’t come cheap, though. In addition to the iPhone itself, the device retails for $179.95. To use it, you’ll need to download the free GoPayment app from Intuit, which carries a $12.95 monthly fee, plus swipe fees (a high-volume plan is also available with no monthly fees but higher swipe fees).

San Diego-area residents can find the tech-savvy Girl Scouts (and their cookies) at the location and times listed here. The rest of the country will have to wait until next year to see whether the program rolls out nationwide.

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