The national lottery, which will be operated by the Camelot Group, is bound to be a runaway success. Most people will ignore the odds of millions-to-one against hitting the jackpot and see instead the riches pouring from the sky.

For another section of the betting public, however, the long odds are more likely to be a temptation, as they like nothing better than a strange bet that they stand virtually no chance of winning.

Bizarre bets have opened up a new market for bookmakers, who regularly receive letters from people wanting to bet on their children winning Wimbledon, Doctor Who being the next England manager, or Norman Lamont being revealed as an alien. Clearly the main object of such bets is not to win money. 'A lot of it is bravado,' says Ian Wassell of Ladbrokes, 'so people can say to their friends in the pub: 'Look what I got from the bookmakers.' It's a conversation piece.'

The appeal to the bookmakers is clear: although such wagers contribute little to turnover, they provide enormous publicity - and the bookies have recently started coming up with some weird bets of their own.

Some of the longer shots recently available at Ladbrokes include Linford Christie to become a permanent member of the Chippendales (500-1), Welsh soap Pobl y Cwm to top the television ratings (1,000-1), and Mr Blobby to give the 1994 Queen's speech (50,000-1). This last price shortened to 10,000-1 when someone risked a few pounds on it.

Stranger still are the people who write in with requests, such as the Derby man who bet that Princess Margaret would marry Burt Reynolds within five years (1,000-1), or the Yorkshireman who wagered pounds 100 that extraterrestrials would be running Earth by 18 January 1994 (10,000-1).

Ladbrokes recently received a letter from a 20-stone man wanting to bet on himself to run a four- minute mile by the year 2000. 'We were quite keen on that one,' says Mr Wassell. 'We met the chap and have had various discussions. Next we will do some physical tests and check his background, to see whether he was the AAA national marathon record holder. We do as much research as we can, but there are some things you can't investigate. Instinct is the best way to describe it, although I know that's not terribly scientific.'

Ladbrokes will take bets on virtually everything except matters of life or death (hard luck, Elvis resurrectionists). They also draw the line at anything which could lead to people hurting themselves, and 'bad taste' bets. Recently disappointed in this last category have been inquirers for odds on Michael Jackson going to prison, and the number of bodies to be found at 25 Cromwell Street, Gloucester.

Very few long shots make it anywhere near the winning post, although there have been some exceptions. William Hill got its fingers burnt with an early foray into the long-shot market, when one David Threlfall staked pounds 10 at 1,000-1 that a man would walk on the moon by 1970; he won pounds 10,000. Graham Sharpe, of William Hill, who has compiled a book of desperate, perverse and foolish wagers (Bizarre Bets, Virgin, pounds 4.99), says: 'Some are like time bombs waiting to explode in 10, 15 or 20 years' time. The first one that stands any chance of coming off will be Curtis Robb, who ran for Britain in the 800 metres at the last Olympics. His dad had a pounds 200 bet with me at 500-1 that he would win the 1,500 metres in the next Olympics, and I would say he now has a 5-1 chance.'

Ladbrokes will only offer 14-1 on aliens reaching Earth by 2000, simply because so much money has been wagered. The odds on Nessie tiring of hide-and-seek are slightly longer at 25-1, following the revelation that her most famous picture is a hoax.

But for the next person to emulate Mr Threlfall's far-sightedness, or even the first national lottery millionaire, life is unlikely to change much, according to Dr Paul Webley, a psychologist. 'Apart from a period of re-adjustment, where people move to a bigger house or give up their jobs and lose their friends, people just get used to having more money. It doesn't make them any happier or unhappier.'