Cash participants were unable to purchase anything online during the experiment, and MasterCard participants had to pay their landlords in cash.

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In fact, the reason why this ill-fated security company went after Anonymous was because they brought down major online businesses: PayPal, Amazon, Mastercard.

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Mastercard announced this week its development of MasterPass, an online and cashier payment app.

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To the extent that PayPal and Checkout help to move cash and cheque purchases online, where they are subject to transaction fees, Visa and MasterCard welcome them.

ECONOMIST: Online payments

The company points out that customers can't bank with the card or use it outside the U.S. But other stored-value cards, often branded by Visa or MasterCard, can be accessed for cash via atms worldwide and reloaded with cash online or at checkout counters without a bank account or face-to-face identity verification.

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If such a card were to be introduced, explained Matthew Mayo, Mastercard's head of business development in the UK and Ireland, claimants could be blocked from using online gambling sites, for example, but not from buying booze at a supermarket.

BBC: UK Politics