Aside from selling phones, one of RIM's key sources of cash in recent years has been service fees generated by BlackBerry users and carriers.

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The A380, the largest passenger plane ever made, has generated more than 100 orders from carriers worldwide.

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Carriers could presumably share the revenues generated by Google's keyword-based ads.

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Among other things, YMax generated revenue by collecting call termination fees from other carriers.

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The carriers think that business can boost their average revenue per user (ARPU), which is now mostly generated by voice services.

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