By Kevin Peachey
Personal finance reporter, BBC News
It can be frustrating when the "computer says no"
Many people have suffered the embarrassment of having their payment card rejected in the shops - but imagine if that happened when you were buying a Ferrari.
That was the case for Mark Taplin, of High Wycombe, on Tuesday when he was just about to get hold of his dream car from a dealership in Birmingham.
But he said he timed the shopping trip at just the hour when a hardware failure brought down some of Barclays' banking services.
"Trust this to happen the only time in my life that I'm ever likely to buy a Ferrari. I'm not amused," he said in an e-mail to the BBC News website.
A faulty "disc array" left 1,500 Barclays' cash machines down throughout the afternoon, primarily across the south of England. Telephone and online banking services were shut down for a few hours and there were reports of some customers being unable to use chip-and-pin services in shops.
Queues developed at bank counters and Barclays' customers found they were unable to use other banks' cash machines.
Barclays is not the only bank to have suffered from a technical glitch that affected banking services. Earlier in the month, Nationwide customers found they were unable to access their online accounts for a day.
Both banks apologised and fixed the problem in just a few hours, but such is our reliance nowadays on our plastic cards that day-to-day tasks suddenly seemed impossible.
"I went into a supermarket to purchase nappies and formula for my children, only to be told my transaction had been declined," wrote Jeanette Thomas, of Gosport, during the afternoon.
"Now stuck, no formula, and no nappies - not to mention the embarrassment caused by being declined."
Others reported sweating over some one-off payments that they were unable to make while the fault was being fixed.
June Grant, of Shaftesbury in Dorset, said she was trying to book a coach to transport guests at her daughter's forthcoming wedding.
Some readers said they were trying to book flights, and Dr Richard Deloughry said he was touring cash machines in Manchester trying to get some cash ahead of leaving for a wedding in the US.
Help at hand
Yet some of the comments from BBC News website readers are rather warming and suggest that the spirit of community is not dead.
Some high-value transactions were delayed by the glitch
One reader in Nottingham borrowed money from her boss to buy her lunch. Jo Hart, from Kenilworth, said staff in the new beauty salon in her neighbourhood were happy for her to pay the following day.
And one reader in Cheam was particularly grateful to the coffee shop manager for allowing him credit of £3.49.
"I hope this is resolved... because I don't think Michael's good nature will stretch beyond another day. Although he looks as though he has a long fuse, he can be quite fierce looking," he said.
Payment of a taxi fare was delayed for Scott Ramsier in Bournemouth, who was on his way to an exam.
On the more serious side, some small businesses found they were unable to make payments to suppliers, delaying transportation, and were demanding compensation from Barclays.
A Barclays spokeswoman said that anyone who incurred charges from any organisations as a result of late payments should contact the bank to claim a refund. This was standard procedure if there was a technical error, she said.
With the global financial crisis fresh in the memory, some customers thought - wildly incorrectly - that the bank might have gone bust.
In fact, these episodes have shown us how successful the switch from cheques and visiting the local branch to online payments and card transactions has been.
None of the people caught out on Tuesday seemed to have a chequebook with them and many were thrown without instant access to their cash.
Barclays is leading the way on contactless technology - when a plastic card is pressed close to a sensor to pay for something, rather than using cash.
Mobile phones are expected gradually to become an electronic wallet. The number of non-cash transactions is predicted to overtake cash payments in the UK by 2015, according to the payments association Apacs. The cheque is said to be in "irreversible decline".
Opponents of this reliance on electronic chips, rather than cash and paper cheques, will point to the episodes this month as evidence that the technology needs to be faultless before such a cashless society could run efficiently.