This time next year, the pain will have passed. You'll have paid €1.27 for the newspaper you're reading and will be nursing a takeaway coffee that cost a few cents more. You'll have fed coins worth around the same into a parking meter for the pleasure of parking your car, having stopped at the service station to pay €44 for your weekly fill-up. And, despite your current doubts, it will all have been the most natural thing in the world.

But this time next year, we'll be eight long months into using and abusing a new currency. It's the early days when things are going to be harder.

The plan is that the transition will be seamless but let's play devil's advocate and presume that gremlins do manage to enter the system. It could be at the most mundane of levels: automatic ticket machines not being able to accept euro coins or vending machine not spitting out the required product.

Although we have little reason to suspect that such problems will occur, they are a definite possibility.

At the bottom of much of the potential chaos is the Irish love of cash. The Republic is the second-highest coin user in the euro zone and this will make life difficult next year for customers and operators of cash-based businesses.

Think of the inebriated reveller on New Year's Eve who, upon buying a pint a minute after midnight, should technically receive a pile of shiny, unfamiliar coins in his change. Several pints later, the same happy reveller enters a fast-food emporium and, after spending several minutes fumbling for change, attempts to purchase his cheeseburger with a combination of euro and pound coins.

With both currencies legal tender until February 9th, the fast-food vendor cannot refuse to accept the offer, but confusion and delays will be hard to avoid. Supermacs, the Galway-based fast-food restaurant operator, is considering foregoing profits and closing shop until the next morning. Public transport has been identified as a greater potential euro nightmare than many other sectors.

Around 80 per cent of Dublin bus fares are tendered in cash, with customers throwing coins into a mechanical slide that links to a storage safe below. The slide is transparent on one side, allowing drivers to view the coins tendered. If an amount greater than the exact fare is offered, drivers issue a paper IOU that can be cashed in at Dublin Bus offices.

The company has not yet finalised its strategy for dealing with the particular issues surrounding the dual-currency period, but a spokesman admits there is "no perfect solution".

Bus drivers will suffer the brunt of the stresses involved: they will have to train their eyes to identify the front and back views of eight new coins, with the added difficulty that euro coins do not have a numerical denomination on their reverse side. They may also be asked to accept mixed-currency fares and calculate how much a resulting IOU should be, all within a window of a few seconds as commuters invariably rush to reach their destinations.

It has been estimated that issuing a ticket could take up to four times longer than usual next January.

The National Taxi Drivers' Union, meanwhile, is concerned that the meters of its 6,700 Dublin drivers will not all be ready to accommodate euro fares from January 1st. To do this, meters have to be opened, reset and then resealed by the Legal Metrology Service.

According to the Union, "pandemonium" could ensue if this process is not started soon, particularly since a fare increase that would necessitate the same procedure is expected in coming months. And this is before training drivers in a new currency is even considered.

Then you have the January sales, a tradition that makes the first few weeks of any year a period of heavy spending. Dublin-based department stores Arnotts and Clerys both plan to run their sales as normal next year, meaning staff will have to prepare price tickets with four amounts: the old and new price in two currencies. An Arnotts spokesman is confident that confusion will be kept to a minimum.

The changeover will be far from simple but it should be emphasised that the problems outlined above are all simply a possibility. The Euro Changeover Board expects the main pain of the changeover period to have been beaten within the first two weeks. However, it could seem like a long two weeks.