I've decided I need a bit of a break. I quite fancy seeing more of Europe, so first I am flying to Ireland for a few days, then to Sweden and Norway. I'm looking forward to it.

These three return flights from London have cost me about $12 because the airline is kindly offering to pay my passenger tax. It costs me more than that to take my kids to the swimming pool for an hour. Isn't that fantastic?

One of the great low-cost flight innovators is Stelios Haji-Iannou of Easyjet. He developed the idea of yield management for air travel. Basically the price of the seat is determined by the demand, so booking in advance is much cheaper than at the last minute. It is an effective and profitable model which has been exported to all parts of the world.

Of course, we all know that this has had a dramatic effect on greenhouse gas emissions.

Cheap flights, globalisation and the mounting cost of train travel have made aviation by far the fastest growing source of carbon dioxide in the UK.

Emissions from UK aviation have increased by nearly 70% since 1990 and rose by 11% in 2004 alone. While they amount to less than 3% of national carbon emissions, expected growth will nearly double this within 25 years. -- Guardian

Well, the answer is that I'm not going on a European trip. Yes, I've bought the flights, but I am not going to use them.

For one thing, by buying the cheapest fares, I'm inflating the prices for everyone else. If the flights are more expensive, then maybe people would have second thoughts about using them as cheap public service transportation.

For another, the cheap airlines make money by charging for 'extras' such as luggage, food and check-in counters. If I'm not there, the only money they've made from me is the $12, which barely covers processing my card details.

And, before anyone says so, yes I appreciate that my vigilante efforts are going to have a limited effect on a multi-billion dollar industry. But, imagine the effect if a large group of committed environmentalists bought all of the cheapest tickets when an airline had a cheap offer, and then refused to fly. Airlines would eventually see the effect on their bottom line of flying planes with fewer paying passengers; airports might have to close, people might eventually drift back to more sustainable forms of transportation. As well as penalising airlines for flying empty aircraft, we need to make those that do fly considerably less profitable.

The other great advantages are that it is perfectly legal and almost undetectable. What would happen if a large group checked-in online and then did not turn up to the aircraft?

Imagine if an underground movement managed to reshape the airline industry. Wouldn't that be an accomplishment?