The cups are a classic white porcelain design by Matteo Thun (the man who gave us the Swatch), and they have recently become the canvas for decoration by some of the great names of modern art, including Robert Rauschenberg and James Rosenquist. Much in demand by collectors (one limited, signed Rosenquist edition has reputedly changed hands for three million lire), the cups are a statement by gourmet espresso coffee-makers Illy - major sponsors of the Biennale - about the long romance between coffee and culture.
It's a relationship that dates back to the Arabs of Mecca a thousand years ago. They established the first ever coffee houses that flourished as venues for conversation and chess, music and dance. As coffee spread through the Middle East (unlike alcohol, it was an acceptable drink for Muslims), the Constantinople coffee houses of the 16th century became renowned for their luxurious decor, their political debate - and radical ideas.
It was the Venetians who brought coffee - known as "Arabian wine" - to Europe at the beginning of the 17th century, where it was hailed as "the devil's work" by those nervous of its subversive image. Fortunately, Pope Clement VIII declared it to be a "true Christian drink", and so the tradition of coffee houses as places of culture and conversation continued their spread across Europe.
Then, as now, the coffee house was the ultimate place to hang out, and so ambience was all important. Venice's Cafe Florian (founded 1720) in the Piazza San Marco, still has that intimate but public, relaxed but elegant style of so many good modern cafes. These were places - and still are - for artists and writers to meet, read the newspapers and argue about politics and ideas, their brains buzzing with caffeine.
England's first cafes were in Oxford in the mid-17th century and one of these evolved into the Royal Society. Similarly, the origins of Lloyd's of London lie in the Lloyd's coffee house in Tower Street where the proprietor used to provide lists of the ships insured by his clientele.
And while the English are still principally tea drinkers, fresh ground coffee is still the drink of the cosmopolitan, the cultured and the conversational. Modern coffee houses - from cybercafes to Italian espresso bars - are booming in Britain's current coffee revolution. Meanwhile the coffee cognoscenti grow ever more obsessional about the finer points of a good cup of coffee, its roast and its rituals, their enthusiasm sharpened by the craving for caffeine that is now the most widely used drug in the world.
Coffee tasting, like wine tasting, is considered an art in itself with its own elaborate vocabulary and exotic equipment. The coffee "liquorer" (taster) has a special "goute cafe" (round silver spoon) to dip into the fresh brew - which is strictly without milk or sugar. Flavour, body and aroma are judged and graded as the experts roll the coffee around their tongues before spitting and rinsing with milk. They never taste more than a dozen samples a session however, because coffee has a mildly anaesthetic effect on the taste buds.
Dr Gianfranco Brumen is quality supervisor for Illy and a taster with 25 years' experience. He avoids cigarettes and spicy food all week to keep his taste buds in trim for the task of tracking down any one of a long list of "negative flavours" among the coffee beans. These have very specific and evocative descriptions such as "stinkers" (an over-fermented sulphurous smell), "rancid" (from decayed oils that taste like corks in wine) and "fauna" (the odour of the skin of a wet, wild animal).
Just one bad bean in the 50 needed to make a cup of espresso can ruin the taste of the whole brew. But checking and choosing the beans is only the beginning. Then comes roasting, which has another vocabulary all its own (light roasts are "half city", "cinnamon" or "New England", while dark roasts can be "New Orleans" or "after dinner"), followed by the various grades of grinding ("coarse" to "fine espresso" to "pulverised").
And all this before you actually get round to the crucial and contentious ritual of making a cup of coffee. According to Jon Thorn's Coffee Companion, coffee perfectionists will use only freshly roasted beans not more than a week old, stored in airtight containers and ground immediately before brewing. The water must be fresh, drawn from a cold tap that has been run for several seconds, then boiled - but not overboiled. The water (no longer boiling) must be poured into the coffee maker of your choice (he favours the cafetiere), left to brew and drunk as soon as possible - but only from a warmed cup.
An art indeed. And, as it happens, winner of the Illycaffe award for young talent at this year's Biennale is the British artist Sam Taylor- Wood with her audiovisual installation Bad Trip, which represents a scene from a crowded London restaurant. Maybe her cup of coffee had one bad bean with the odour of the skin of a wet wild animal...
From the beancounter ...
80 per cent of coffee drunk in the UK is instant coffee.
The world's biggest coffee drinkers are the Swedes (11 kilos of coffee per head each year), followed by the Norwegians (9.10), the Danes (8.75) and the Finns (8.65). The Americans are a paltry 13th (4.02), while we in the UK are 15th (2.27).
World coffee prices went up by a quarter in 1995 due to a doubling of the cost of raw coffee beans. The surge in demand on international markets has made instant coffee a target for shoplifters across Britain who trade in jars of coffee to pay off debts.
75 per cent of the world's coffee is made from arabica beans which have a richer taste and lower caffeine content than robusta beans.
One legend has it that coffee was first discovered by an Ethiopian shepherd who noticed that his sheep became extremely lively after eating the berries of the coffee plant. `The Coffee Companion: the connoisseur's guide to the world's best brews,' by Jon Thorn. Apple pounds 15.