Amazon.com has placed lockers in stores where customers can pick up their packages.

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Amazon has been installing similar lockers in malls and convenience stores in such cities as Seattle, New York and San Francisco since 2011.

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OK, so what about cloud lockers from companies like Amazon.com (Nasdaq:AMZN)?

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After launching its pick-up lockers nationwide in 2012, Amazon is trialing same-day delivery in 10 urban centers.

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Lockers is "an interesting experiment for Amazon, though it's not clear it will be a huge business for them in the U.S., " said Brian Walker, a Forrester Research analyst.

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Amazon avoids much of that with guaranteed delivery to its lockers, often housed in locations operating 24 hours a day.

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As well as old-school doorstep couriers, Amazon also offers collection at local shops such as Spa, as well as from security code-controlled lockers.

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