Gilbert and George put free artwork on internet, Guardian

An original work by artists and national treasures Gilbert and George would normally set you back many thousands of pounds. But from 11.30pm tonight a piece is being made available to anyone who wants it - for free.

The work, called Planed, can be downloaded from the Guardian and BBC websites from 11.30pm, for 48 hours only. It will be the first time that artists of this stature have made work available in this way.

In line with the practice of Gilbert and George over many years, it consists of a number of panels. Members of the public must download each of the nine panels to create the full artwork, which can then be printed off, at any dimension, and assembled. There is no limit to the number of times the work can be reproduced.

The title refers to the plane tree, with distorted images of its leaves and fruit forming the background. It is a tree particularly associated with London and it is the texture of London streets, from road signs to graffiti and newspaper billboards, that has informed most of Gilbert and George's work for 40 years.

As with all their work, the piece also includes images of the artists themselves - in this case neatly suited and booted, but distorted like images seen through a kaleidoscope.

The creation of the downloadable work was the idea of Alan Yentob, who tonight presents an edition of the BBC arts programme Imagine about the artists. "This sort of thing has never been done before," said Yentob, "But when I saw how Gilbert and George made their pictures it was clear that this would be a perfect match."

The artists, who used to manipulate photographic images by hand, have, over the past few years, begun to work with sophisticated computer technology. "When I put the idea to them they were immediately enthusiastic," said Yentob. The notion of a freely available artwork, he added, fitted perfectly with the artists' long-held ideal of "art for all", a principle that has formed the bedrock of their practice since they started working together in the late 1960s.

Gilbert and George rarely produce work in editions, and have never done so for free before; Planed thus represents the most wholehearted manifestation of "art for all" of their career.

Gilbert was born in the Dolomites in Italy, in 1943; George in Devon in 1942. They met as students at St Martin's School of Art in London, where they formed the most enduring and famous partnership in British art.

They adopted an identity as "living sculptures", which they retain, becoming both the subject and object of their art. Their reputation was established in 1969 when they created Singing Sculpture, in which they stood on a table and sang the Flanagan and Allen number Underneath the Arches.

That year they published the Laws of Sculptors, which stated that they would be "always smartly dressed, well-groomed, relaxed, friendly, polite and in complete control" - another principle strictly adhered to over the years.

Gradually, the artists developed a method of working with photographs, eventually devising their grid system.

Their work has always had a reputation for containing shocking and explicit material, though they have always denied that they are deliberate provocateurs, but rather, artists who depict the human condition as it really is. Works such as The Penis (1978), Rose Hole (1980), Sperm Eaters (1982) and Shitted (1983) caused a frisson in the art world and beyond. Their Dirty Words Pictures (1977) "packed a violent punch whose aftershocks continue to be felt today", according to critic Michael Bracewell.

For more than 30 years the artists have lived in Spitalfields, east London, and their neighbourhood has inspired much of their work. A recent set of works, exhibited under the name Sonofagod Pictures: Was Jesus Heterosexual (2005), tackled religious fundamentalism, one work emblazoned with the words: "Jesus says forgive yourself. God loves fucking. Enjoy!"

Their most recent work, shown for the first time at Tate Modern in the major retrospective just ended, dealt with terrorism and fear in the capital, using Evening Standard billboards to create works called Terror, Bombing, Bomber, Bombs and Bombers.

· Imagine is broadcast tonight at 10.35pm. After the programme, Planed will be available to download at bbc.co.uk/imagine and Guardian.co.uk/art