In the UK most people now use 'chip and pin' debit cards - you put your card in a handheld machine, type in your pin number, and your account is debited automatically.

What if the card had a numeric LCD display, a cheap infrared transceiver and a numeric keypad ? The keypad would have two extra buttons - 'pay' and 'receive'. You would 'charge' the card with money by putting into an ATM machine.

When you wanted to pay someone, you'd each type the amount into your cards, then hold them together; you'd press 'pay' and they'd press 'receive'. Your card would be debited and theirs would be credited. If there was a difference in the two amounts, the payment wouldn't go through.

The next time you stick your card into the ATM machine, any increase would be credited directly to your account - the equivalent of paying cash into the account.

Security issues would be interesting to consider. You could type in a PIN number every time, or else use a thumbprint sensor (complex/expensive/bulky). There could maybe be a 'panic' button that caused the card to irreversibly fry itself, in case of mugging. Standard anti-fraud mechanisms from the current chip&pin systems would still apply.
-- bumhat, Jan 03 2006

Nice idea, but pretty much preheated in sci-fi.
-- normzone, Jan 03 2006


are you proposing we stop using cash? if so, how do i pay my dealer? if not, how is this system better than cash plus debitcard?
-- rainbow, Jan 04 2006


<aside>[bumhat] did you have anything to do with the Massive attack visuals ? they were amazing</aside>.
-- neilp, Jan 04 2006


[neilp] yeah, we did them in 2003 and 2004... thanks
-- bumhat, Jan 04 2006


what about small, very light, and universally accepted pieces of paper with images, graphic swirls and unique numbers printed on them? When you are drunk or feeling flash you can also use set fire to them.
-- xenzag, Jan 05 2006



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