When Susan Walker watches the Wimbledon final today, it will be on a giant wall-mounted plasma television. It’s a monster of modern technology and worth £3,200. Walker, a 22-year-old veterinary nurse, bought it for just £1.55.

Impossible? That’s what she thought at first.

Her chance to bag a bargain began out of the blue when she received a text message on her mobile inviting her to enter a reverse auction.

“I checked out the company’s website and saw it was all genuine so I put in a bid,” said Walker who lives in Broughton, Lincolnshire. There was a small charge, but she was happy enough to ante up. A week later she learnt the bargain television was hers. “I thought they were winding me up when they told me I’d got it.”

Perhaps not surprisingly Walker, who had previously used the internet to buy phones and clothes, is now a devotee of such auctions. Her friends have also started placing bids in the hope of similar coups. So are many thousands of other people and Walker is far from the only one to have bought the latest entertainment gizmo for less than the price of a jar of coffee.

Want a £400 portable DVD player? Yours for 79p. An Apple iPod? To you, sir, for £2.80. Tickets to see Manchester United on their forthcoming tour of America? To the young lad in the red top for 65p. These are just a few of the recent bargains.

One of the latest auctions offers a £110,000 Bentley Continental GT for sale. Someone will drive it away this summer for less than £1,000, guaranteed.

Of course, there is a catch and it’s not quite as simple as it sounds. In a reverse auction, you can’t just enter the lowest bid and win: otherwise everyone would simply bid 1p. What you must do is enter the lowest “unique” bid.

Say 90 people bid 1p for an item, 50 bid 2p and 30 bid 3p and so on. But say only one person bids 4p: that bidder is the winner.

Though the item might go for mere pennies, the seller aims to make a profit because everyone has to pay a small fee to enter the auction. It is a price an increasing number of people are willing to pay.

Andrea Eniks, a manager at QXL, an internet company that organises reverse auctions, said: “Everyone likes to bid and there’s the anticipation with this that you might pick something up at a fraction of the usual price.”

Is it all too good to be true? Perhaps. Critics warn that people should be wary. Though such sales may be billed as auctions, they say, in many ways they are just a new form of lottery — and the odds can easily be stacked against the bidders. The real winners are likely to be the auction companies.

ONLINE bidding mania began in September 1995 when Pierre Omidyar, a technologist in Silicon Valley, wanted to sell a broken laser pen and wondered how best to do it. He set up a mini-auction site on his personal web page.

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