Wish you were it: seeking art on a postcard

Could it be that the surrealist egg box with an entwined papier mâché knife is Tracey Emin's latest take on modern life? Is the swirly scribble Damien Hirst's new attempt to beguile the chatterati? Or might the cartoon of Gordon Brown cheerfully knifing Tony Blair in the back be Sonia Rykiel's idea of a joke?

These, and other matters of aesthetic detective work, will be foremost in the minds of aficionados when they queue tomorrow to view Britain's annual lucky dip for a small but perfectly formed bargain masterpiece. The doors will open on Secret, a show of serried ranks of 10.5cm-by-14.8cm postcards which raises funds for the Royal College of Art (RCA) in London by mixing the work of students with pieces by around 20 big-name artists, designers and celebrities.

The college said yesterday that it had received 2,700 cards, the highest number since the event started 12 years ago - an increase of nearly one-third on last year.

Among the high-profile figures whose work will be hidden on the shelves this year are a crop of first-time contributors including the photographer David Bailey, fashion designer Sonia Rykiel and Olafur Eliasson, whose sun-like installation at the Tate Modern, The Weather Project, won rave reviews.

A spokeswoman for the RCA said: "This is the most cards we have ever had. We've had to open up extra exhibition space to accommodate them. The event is increasingly popular, not only because of the chances of buying a Tracey Emin or a Damien Hirst, but also because you might be buying something by a star of the future."

Since its inception in 1994, Secret has become an annual festival of guesswork by novice buyers and cunning endurance by a savvy few to bag the most sought-after works in the artistic lottery. The authors of the postcards, each costing £35, remain anonymous until they have been bought by their new owner.

Those fortunate - or shrewd - enough to pick out a postcard by a renowned artist, such as Sir Peter Blake or Turner Prize winner Grayson Perry, will see the value of their purchase rocket. Most are happy to make do with the thought that if they do not pick out a Wolfgang Tillmans or a Quentin Blake, they at least have a work they like and have made a contribution to a worthy cause. So far, Secret has raised more than £600,000 for the college's fund to support students.

Others, however, take the matter more seriously. Last year, an anonymous couple camped for a week on the steps of the college to secure the right to be first in line. Once inside, the astute pair proved their worthiness as bargain hunters by picking out the only two David Hockneys in the exhibition - and then added cards by Perry and Hirst.

The search for a Hirst, Blake or Hussein Chalayan has been further complicated in recent years by known artists deliberately disguising their style and students seeking to mimic them.

This year potential buyers attending viewings until next Thursday, ahead of the sale days next Friday and Saturday, will have the chance to pick out works by established names such as the leading American photographer Nan Goldin and alternative figures such as the former Blur guitarist Graham Coxon.

Anyone hoping to secure a tip from attendants supervising the show should think again.

The names of the artists are known to only half a dozen people, none of whom go anywhere near the exhibition.