In a clever piece of self-promotion, the budding 34-year-old electronics entrepreneur had just pulled off what has recently been nominated one of the most imaginative April Fools pranks: the great Sydney Harbour iceberg hoax. What's more, it cost him only $1200, for the hire of a barge, and the purchase of a big sheet of white plastic and lashings of fire-fighting foam. Several dozen cans of shaving cream - used to complete the Dickenberg One, as it was dubbed - had been provided free by a manufacturer.



"The funny thing was that for months I'd been planning to go down to Antarctica and tow some real icebergs back," Mr Smith recalled this week. "We were going to do experiments and see if they could be used to provide fresh water for places such as Adelaide.

"The media were always on to me. When am I going to do it? Anyway, someone on my staff came and said, 'Well, why don't we just fake one for April Fools Day?' So that's what we did. "On the Friday I announced that the iceberg would be arriving some time in the next week - to say it was coming the following day [April Fools] would have given the game away." At 3am a fellow inventor and collaborator, Hans Tholstrup, towed the barge out through the Heads, and, secretly under cover of darkness, the iceberg was built.

Two hours later, as Mr Smith boarded the iceberg, 300 of his employees started ringing local radio stations and newspapers. "'What's that thing coming through the heads?' they asked. 'It looks like an iceberg."'

Smith still chuckles at the reaction. "Switchboards were jammed and by the time we towed the barge in the headlands were covered with people. The navy even rang to offer us somewhere to moor." In retrospect, the prank looks amateurish. Though Mr Smith was approached by boats demanding chunks of ice, or "Dicksicles" as they were called, within hours driving rain had "melted" much of the foam and cream. Perhaps you had to be there. Alex Boese, an American specialist in pop culture was not, but he is still impressed.

This month he placed The Great Sydney Harbour Iceberg at number 12 in his top 100 list of April Fools Day pranks and practical jokes and included it in his new book, Museum of Hoaxes. "Yeah, it was a good one," says Boese, who insists that, while the world may seem a gloomy, unfunny place right now, we are living in a golden age of hoaxes.

Quite when April Fools Day - which falls on Tuesday this year - began is in dispute. Some experts trace it back to Roman times, others to the adoption of the Gregorian calendar in the 16th century. Some jokes - such as sending an apprentice out to buy striped paint, ringing the zoo to speak to Mr C. Lyon and, in France, taping a paper fish (the poisson d'avril) to the back of a friend - have become April Fools traditions, and were long ago played out through the media long ago. Inevitably, some April Fools are simply not funny, some are downright irritating and a few cause embarrassment and even panic. A report of killer wasps attacking Auckland alarmed residents. A story that Canada's finance minister was quitting to breed cattle sent the dollar plunging. In 1995 the Salvation Army in Australia was forced to pulp 20,000 copies of its weekly newspaper War Cry after editors belatedly decided that an April Fools Day joke that John Howard had abolished Easter holidays was in bad taste.

Over the years the ABC has broadcast several spoof stories about such things as the Dylofish rod (see panel), mining at Uluru, and plans by Australia to adopt metric time whereby the 12-hour clock would be divided into 10. But Dick Smith - who later introduced the microdot Pric (a PRinted Integrated Circuit that when attached to speakers and doused with lemon juice became a radio) and had double-decker buses jump over motorcycles in a reverse of Evel Knievel - fears that we may have lost our sense of fun.

That, or the world has - temporarily at least - become such a confusing place that we can no longer work out what is fact, what is fiction, what we can laugh at, and what we can't. Top 10 April Fools hoaxes

1. SPAGHETTI HARVEST Bogus item on 1957 BBC news show Panorama. Viewers seeking advice on growing their own were told to put spaghetti sprig in tin of tomato sauce.

2. SAN SERRIFFE Guardian newspaper published seven-page supplement celebrating the Indian Ocean republic. Its two main islands were Upper Caisse and Lower Caisse, and its capital was Bodoni. 3. PI IN THE SKY New Mexicans for Science and Reason newsletter said fundamentalist Alabama state lawmakers had cut maths concept pi from 3.1415 etc. to "biblical value" 3.0.

4. TASMANIAN ROCK WALRUS Floridans rushed to buy these new "pets" after newspaper reports that they looked like a walrus, purred like a cat, had the temperature of a hamster and ate cockroaches. 5. WHISTLING CARROTS British supermarket chain Tesco advertised new GM vegetables with special tapered air holes that whistled when the carrots were fully cooked. 6. KIWI WASP SCARE New Zealand DJ told listeners to tuck trousers in socks and set honey-baited traps outside their front doors because a mile-wide swarm of wasps was headed for Auckland.

7. TURNING JAPANESE English-language newspaper produced a special "Not the Japan Times", featuring story of a Japanese politician under scrutiny for not taking bribes. 8. PHONE SEX A German newspaper reported separate phone kiosks would be introduced for men and women because women stayed longer.

9. SOMETHING FISHY ABC's This Day Tonight trialled special Japanese rod and reel that enabled anglers to catch the fish of their choice by calling up its number on a dial. 10. SMELLOVISION Breakthrough invention demonstrated, by brewing coffee and chopping onions, on BBC in 1965. Source: www.museumofhoaxes.com