While in London, some of the bidders will go talent spotting at Cabaret Mechanical Theatre in Covent Garden, the showcase for masters of British contemporary automata - miniature hand-cranked tableaux full of wit and the unexpected that are the latest expression of British comedy.
Even at Cabaret, American and Japanese buyers far outnumber Brits. An American this year paid pounds 4,000 for an automaton sold new 10 years ago for pounds 75 by the foremost British maker, Paul Spooner. It is a cheeky carved model of Manet's reclining nude Olympia with articulated, undulating torso and with a jackal-headed figure shakily serving her Camp coffee. The tiny world of automata seems to be yet another niche in the British collectables market that foreign investors have invaded under our noses.
Sue Jackson, founder of Cabaret Mechanical Theatre, has a mailing list of 600 would-be buyers, mostly abroad, and standing orders from a score of them. She has for sale a customer's Spooner Olympia, from the original edition of 24, for which pounds 1,500 has been offered - but she is holding out for more. None of Spooner's latest flight of fancy, Hungry For Love - a cutlery-banging sailor awaiting a pair of pink wobbly jellies served by his wife from a moving hostess trolley - will appear in Cabaret's Christmas mailing list: the entire edition of 10 has already been snapped up at pounds 600 each.
Patrick Rylands bought an Olympia for under pounds 2,000 by postal ballot shortly after the top price of pounds 4,000 had been paid. That demonstrates the unpredictability of a market consisting of just a handful of avid collectors. Once the main players have all got their Olympia the price drops. Mr Rylands, who collects mainly Spooner, says: "Automata are vastly underpriced. I still find it remarkable that you can pay as little as pounds 100-pounds 500 for objects that have left the craft world behind and come close to art".
Would-be collectors with less than pounds 100 can solace themselves by paying a modest pounds 32.75 at Cabaret for a copy of Peter Markey's wooden peeing dog (lifts hind leg), pounds 39.95 for Keith Newstead's flying pig (wings and limbs move), or pounds 69.50 for the most popular - Spooner's camel simulator, showing that jackal-headed character getting his bumps: more than 800 have been sold. Cheaper: wooden kits pre-cut ready to assemble and paint, pounds 23.50. Cheaper still: printed card cut-outs (pig pounds 1.95).
An automaton or two can raise a laugh: 60 or so, Cabaret's complement, can make you philosophical. Their automatism is too close to real-life human behaviour for comfort. What, for example, are we meant to make of Newstead's Domestic Bliss, in which Sidney and Elsie Sprogett's daily breakfast-time row is interrupted by the punctual passing-by of dapper Reg from No 26, and in which Woody, the Sprogett's dog, receives a ritual kick under the table? Or Spooner's pair of nodding heads, one compulsively jawing at the other one, who listens in nightmarish incomprehension?
They are quite unlike the sassy, self-possessed Victorian mechanical dolls in the saleroom. These juddering imitations of humanity are hapless victims of circumstance, perpetually foxed and fooled by the Big Machine.
Spooner, 47, an art and design graduate who was for 10 years a van driver, never gives his models' faces expressions, preferring viewers to imagine their own. He cheerfully admits that his automata "represent the empty and cyclic aspect of people's lives - such as putting out the dustbins every Friday".
But machinery, he says, "makes that inevitable". He reels off words for mechanical movement that sound disconcertingly like the nature of life: "repetitive, circular, rythmic, regulation, leverage".
But then, for those fortunate enough to own an automaton, or to bribe one with 20p in the slot, the Machine, whose inner machinations are almost always exposed to view, will reveal the Secret of Life - the "cam". The plywood cam transforms circular movement into up-and-down. If its shape is like a figure six, it will, with each revolution, push a beam or vertical rod upwards and then drop it, causing, for example, a limb to rise then fall.
The part pushed by the cam is called a "follower". It is not the arm that moves the hand that stirs the coffee: it is the crankshaft that turns the cam that pushes the follower that prods the spoon that moves the hand and arm. Come to think of it, the Machine can do without people altogether: one of Spooner's tableaux has the spoons in two cups of coffee stirring eerily by themselves.
Cogged wheels mesh to form gears, speeding or slowing the movement. Coiled springs pull pivoted parts back to their starting point. Together, the cam, the cog and the spring are the three chief governors of behaviour in the world of automata.
Some realms of contemporary art - box art, for example - have started to include moving parts. That of Genevieve Seille, for example, has rollers and secret drawers and sells for up to pounds 2,000. But Cabaret's stock list contains no artist's names and Spooner, though trained as a fine artist, bridles at the word art. "I still like the idea of making toys that you play with and knock about," he says: "I'm not terribly in touch with contemporary art."
Surreal automata may be, but if their makers have a movement it jumps the category of artistic culture. They are a quirky sub-culture of a dozen or so chums wedded to their lathes and jigsaws, whose inspiration owes as much to the mechanic and stage magician as to the artist. Like the 19th-century continental watchmakers who applied their movements to mechanical dolls, they delight in special effects. Spooner's most cherished find was the American textbook Ingenious Mechanisms for Designers and Inventors and he has published his own guides to automata making.
It was Ms Jackson who started them off. After founding Cabaret as a craft shop in Falmouth in 1982 she was dismayed by the banal array of macrame, knitting and pottery boats that greeted her appeal for "anyone who makes anything". But when she displayed Markey's wave machine in her shop, it drew crowds. She encouraged him and Spooner to make moving things.
Take-off came when Spooner's elaborate, near life-size The Last Judgement (skeleton's ribcage containing an escalator of starving, damned, revolving devils eating and playing pool) earned a fiver in pennies during the first hour it was fitted with a slot.Cabaret moved to London, adding on the way such makers as Ron Fuller, best known for his sheep shearing a shearer's head off, and Tim Hunkin, famous for the newspaper strip The Rudiments of Wisdom and the television series The Secret Life of Machines.
Hunkin's lifesize coin-operated automata in glass cabinets outside Cabaret show selected members of the human species back in control. Insert your stockinged foot into the white-coated chiropodist's cabinet and she will incline her head to inspect it, steeple her fingers in contemplation, then drop out of sight. What then happens to your foot is totally unexpected. You could call it a metaphor for life. Most people just scream.
Sotheby's (0171-493 8080). Cabaret Mechanical Theatre, 33-34 The Market, Covent Garden, London WC2 (0171-379 7961), 10am-6.30pm daily except Mondays 12 noon-6.30pm. Museum of Automata, 9 Tower Street, York (0904 655550).