Petrol prices are on the rise again. But canny consumers can still save a few pence per litre if they shop around. Filling up at the cheapest stations can lead to savings of up to £250 a year, according to Fergal Collins.

He should know. Collins and his friend Declan Holmes were so exercised by the variation in petrol prices that they set up a website, www.irishfuelprices.com, to keep car drivers up to date on how much they are being charged.

"I came back from Australia last year and was talking to Declan, who is into web design, so we decided to give it a bash," says Collins. They set up iWonder Creations, a software company, and their website is now attracting up to 200 hits a week.

"We started off putting in the prices ourselves, then asked the public to get involved. We set up a monitor scheme with about 30 people involved on a voluntary basis, and they check prices in their area."

Click on the website and there's a map of Ireland. Click on a county and you'll find the petrol prices entered by concerned consumers. There is, of course, the possibility of people entering bogus prices, but Collins says they haven't had any real problems to date. Prices more than two weeks old are automatically deleted.

So if you're looking for the cheapest price in your area or want to enter a price, try logging on. The difference between the cheapest and the most expensive fuel can be up to 8p per litre.

As for Collins, he usually shops around three or four garages before filling up. "I never just pull into a garage and fill up, unless it's an absolute emergency," he says.

When The Irish Times looked at www.irishfuelprices.com, there was a scarcity of petrol prices, but it also contains a section on heating oils, which lists prices for various providers; a message board and some surveys.

Under alternative fuels, we learn that ethanol was Henry Ford's preferred fuel in the early days of the Model T, while the speed record for an electric car is more than 200 m.p.h.

Right now, of course, most of us are driving cars fuelled by petrol, and the advice of Tom Kitt, the Minister for Labour, Trade &Consumer Affairs, is germane: "Motorists should literally drive by petrol outlets that are not providing good value for money."