Simon Calder: I'm (pretending to be) Lawrence, fly me

The Man Who Pays His Way

Ten years ago, I pretended to be Lawrence Hourahane. Only for an hour, mind, and not for fun. I was indulging in the old traveller's trick of using the unwanted return half of someone else's ticket by impersonating them. On British and Irish flights, as long as you were roughly the right gender, no questions were asked about your precise identity. All was going well until a colleague who happened to be booked on the same flight yelled "Oi, Simon!" just as I was easing myself into the challenging Hourahane role.

Are there any moneysaving tricks left in the airline business? When Concorde returns to scheduled service, you can bet your Gold Executive Card that there will be no more supersonic flights to New York for £150 for people prepared to act as couriers accompanying time-sensitive documents. The ability to stay on board a flight beyond your stop has dwindled, too: headcounts are becoming more common at intermediate airports, so the chances of remaining aboard the La Paz-Lima-Miami flight when your ticket goes no further than the Peruvian capital are slim. And as has been mentioned here previously, Ryanair ­ the busiest airline across the Irish Sea ­ now insists that anyone claiming to be Hourahane/L/Mr must show photo ID to prove their identity.

How about a new trick that will halve the cost of travel for many business flights, and enable bargain-hunting travellers to conduct a whole day's searching in five minutes flat? This week I saw a system in action that does both ­ and threatens to blow traditional airline pricing policies out of the sky.

You will already know that the first rule of travel is that airline fares are infinitely variable, with the corollary that the person in the next seat will always have paid less than you.

You are also aware that most airlines sell restricted return tickets more cheaply than the normal one-way fare. The aim is to persuade discretionary leisure travellers to fill the plane, while ensuring that business customers pay top whack.

And you don't need me to tell you that many internet sites claim to offer the best travel deals on the planet, but finding one that always delivers is rare.

What the traveller needs is a computer system where you tap in your origin and destination, and say what dates and times you want to travel. The machine instantly fires off the request to all the big online travel providers, such as e-bookers, Expedia, Travelocity and Thomas Cook, and also delves into individual airlines' reservations computers on your behalf.

In next to no time, you can pick the lowest fare that meets your needs. That kind of exercise used to take all day on the phone; soon, it will take five minutes. Best of all, the system will encourage you to dodge the airlines' tough fare regulations ­ in short, by turning you into a "Rule Buster".

The system is almost ready. Rule Buster is the name for a remarkably intelligent piece of software. First, it sifts through the hundreds of fares on the average flight. Next, it offers a solution to the annoying reality that the cheapest fares are usually offered on flights that include at least one Saturday night away. Rule Buster will show you how to buy two discounted return tickets, and use them only for one-way journeys. The system will even select a random return flight to help minimise the cost of your journey.

On a standard midweek trip from London Heathrow to Paris Charles de Gaulle, the normal fare of nearly £300 can easily be halved. Rule Buster recommends two round-trip tickets at under £75 each, one starting in London and the other in Paris, with arbitrary dates for the return legs. A couple more clicks take you to the airline or agency to buy. You get half-price travel, in exchange for losing some flexibility ­ the discounted tickets do not usually allow free changes. Easy.

Or, rather, easy ­ the company that runs the system is easyValue, part of the same group as easyJet and easyRentacar. The easyValue idea is to provide "impartial, online price comparisons". It does not hesitate to recommend Ryanair, Go or any other airline if the price is right. But easyJet scores well because, unlike almost all airlines, it does not penalise travellers who want only a short trip. Nor does no-frills rival Buzz. Neither airline's yield management ­ the black art that keeps some fares sky high ­ will be jeopardised by the new system. But other carriers, and the agents who claim a monopoly in fares expertise, yet sometimes seem reluctant to share it, will be furious that the lucrative cat has been let out of the easyBag.

"There are some risks involved", warns Rule Buster, about using two return tickets. To protect earnings ­ and stop passengers taking advantage of the fact that a Milan-London-New York business class ticket is much cheaper than a London-New York one ­ most airlines automatically cancel any booking where the first leg is missed out. Rule Buster gets around this hurdle by making sure that the inbound ticket starts in the appropriate country ­ it suggests combining a London-Paris return on Air France with a Paris-London return on BMI.

Airlines could, in theory, start checking up on "no-shows" and sending them a bill for the difference between the fare paid and the official one-way fare. But bold will be the carrier that risks all the bad publicity by pursuing passengers for payment, when all said travellers would swear that they had had every intention of returning as booked until some unexpected occurrence denied them.

The other option for airlines would be to block easyValue from accessing their sites, and put pressure on agents to do the same. An even less-enticing legal brief than defending Jeffrey Archer would be to defend high-fares principles in the inevitable court battle.

So when will the Rule Buster be available? The system I tried was at the easyGroup headquarters; it is likely to be made public in September. One thing worries me: when every business traveller starts buying cheap return tickets and using them for one-ways, millions of empty seats will be flying around on the return legs. Bad news for the environment. Perhaps a grey market in false IDs will develop, such as the fake $10 student cards sold in Moscow and Bangkok. So if you see me at the airport, just call me Lawrence.