When Chris Bovis, a 26-year-old builder from Tilbury in Essex, was cut off by Orange without warning, he thought a mistake must have been made.
But when the iPhone user contacted Orange and was told he owed close to £19,000, his surprise soon turned to shock and dismay.%VIRTUAL-SkimlinksPromo%
Orange cut off Bovis' services when its attempts to take the huge bill payments from his account were blocked.
When he called to find out what was going on, Bovis was told he had racked up a bill of £8,900 down to unusually high internet usage.
He also told the Daily Mail newspaper that the Orange adviser he was talking to warned him his next bill was due to be another £10,000.
Bovis said: "My first reaction was to laugh, but it stopped being funny when I realised they were totally serious."
Investigations indicate that the sky-high charges were caused by a fault with his iPhone, which meant it started sending and receiving large amounts of internet data in error.
But despite staff at the Apple store agreeing that the phone was faulty, Orange still plans to claim £300 from Bovis unless Apple confirms the problem.
Orange said: "We are happy to reduce the bill to zero as soon as we have received confirmation of the fault from his manufacturer."
Whether Apple will take responsibility for the problem with Bovis' iPhone remains to be seen. But he is far from the only Briton to receive a terrifyingly high mobile phone bill.
The main difference is that almost all the eye-watering bills that have hit the headlines in the past have involved consumers using their phones while overseas.
Back in March 2008, for example, I wrote a piece for The Sunday Times about a City executive who received an £11,000 Vodafone bill after a download of four episodes of the sitcom Friends continued automatically while he was working away in Germany.
And more recently, the Huffington Post reported that Devon-based Anne Roberts was hit with a £27,000 Orange bill after buying a £20 pay-as-you-go phone while on holiday in South Wales.
Like Bovis, her shock bill was caused by a technical glitch, this time on the part of the mobile operator, which charged her account 792 times.
10 of the biggest consumer rip-offs
iPhone user hit with £19,000 bill
Using a mobile phone to make and receive calls, send texts and browse the web while abroad can be extremely costly – especially if you are travelling outside the European Union (EU), where calls can cost up to 10 times as much as at home.
To avoid high charges, Carphone Warehouse suggests tourists ensure a data cap is in place, use applications to check data usage, turn off 'data roaming', avoid data-intensive applications such as Google Maps and YouTube and use wi-fi spots to update social networking sites.
Payment Protection Insurance (PPI) is supposed to help people to continue meeting their loan, mortgage or credit card repayments if they fall ill or lose their jobs. However, policies are often over-priced, riddled with exclusions and sold to people who could not make a claim if they needed to.
At one point, sale of this cover - which was often included automatically in loan repayments - was estimated to boost the banks' profits by up to £5 billion a year.
Now, though, consumers who were mis-sold PPI can fight back by complaining to the bank or lender concerned and taking their case to the Financial Ombudsman Service (08000 234567) should the response prove unsatisfactory.
It could be you, but let's face it, it probably won't be. In fact, buying a ticket for the Lotto only gives you a 1 in 13.9 million chance of winning the jackpot.
With odds like that, you would almost certainly be better off hanging on to your cash and saving it in a high-interest account.
No-frills airlines such as EasyJet may promote rock-bottom prices on their websites. But the overall fare you pay can be surprisingly high once extras such as luggage and credit card payment fees have been added - a process known as drip pricing.
Taking one piece of hold baggage on a return EasyJet flight, for example, adds close to £20 to the cost of your flight, while paying by credit card increases the price by a further £10.
It may therefore be worth comparing the total cost with that of a flight with a standard airline such as British Airways.
Cash advances, which include cash withdrawals, are generally charged at a much higher rate of interest than standard purchases.
While the average credit card interest rate is around 17%, a typical cash withdrawal of £500, for example, is charged at more than 26%.
What's more, as the interest accrues from the date of the transaction, rather than the next payment date, costs will mount up even if you clear your balance in full with your next payment.
Supermarkets such as Tesco and Asda often run promotions under which you can, for example, get three products for the price of two.
However, it is only worth taking advantage of these deals if you will actually use the products. Otherwise, you are simply buying for the sake of it, which is a waste of your hard-earned cash.
Buy a train ticket at the station on the day of travel and the price is likely to give you a shock - especially if you are travelling a long distance at a busy time of day.
However, you can cut the cost of train travel by 50% or more by going online and making the purchase beforehand - especially if you book 12 weeks in advance, which is when the cheapest tickets are on sale.
Other ways to reduce the price you pay include avoiding peak times and taking advantage of so-called carnet tickets, which allow you to buy, for example, 12 journeys for the price of 10.
Most High Street banks offer packaged accounts that come with monthly fees ranging from £6.50 up to as much as £40, with a typical account charging about £15 per month.
Various benefits, such as travel insurance and mobile phone insurance, are offered in return for this fee. But whether or not it is worth paying for them depends on your individual circumstances.