Zero G Aerospace will lose money on its first load of business cards, but once the rocket proves itself, Gonser and Gorrell hope to become the kings of the space souvenir business.

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The cards give free travel on buses and trams, but to get child fares on the Tube and trains parents have to load money onto the cards.

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There are stored-value cards, which allow customers to load money onto a microchip-bearing piece of plastic.

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