A statue for London: The battle of Trafalgar (square, that is)

When it was constructed in 1841, the vacant fourth plinth in Trafalgar Square was supposed to display a statue of a military hero that would enhance the martial splendour of its surroundings. Today, it is a hotly contested platform for artists to showcase ever-more surreal public sculptures that run the risk of being dismissed as headline-grabbing concepts, primarily designed to inspire controversy and little else.

Yesterday's unveiling of the six latest contenders vying for the fourth plinth was, arguably, no exception. As the artists exhibited models of their bizarre submissions at the National Gallery, a stone's throw from the plinth, eyebrows were raised.

Antony Gormley's proposal to winch up 8,760 members of the public, for an hour at a time, to use the plinth as their soapbox was pitted against Jeremy Deller's idea to bring over the remains of a burnt-out car from the streets of Iraq to hoist atop the plinth and Yinka Shonibare's plan to fill the stone statue base with a replica of Lord Nelson's HMS Victory inside a giant bottle.

Tracey Emin's proposal to sculpt a family of meerkats as a symbol of unity and safety appeared positively quaint in relation to the other ideas, which included a 100ft tall illuminated sign reading "Make Art, Not War" in French by Bob & Roberta Smith the professional name of the artist Patrick Brill.

Anish Kapoor, meanwhile, was shortlisted for a structure comprising five concave mirrors (although one had fallen off his small scale model) positioned to turn the world upside down and reflect the sky down to earth.

Gormley, who has made popular public artworks including The Angel of the North, created the greatest stir with his plan, which would need four permanent "personnel" to oversee the project. He hoped that selected members of the public who would apply and go through an interview procedure would feel free to do whatever they chose for their allocated hour.

The Fourth Plinth Commissioning group, chaired by Sandy Nairne, the director of the National Portrait Gallery, and including Channel 4 newsreader Jon Snow, will announce the winner in the spring.

Anish Kapoor SKY PLINTH

According to the artist, Sky Plinth will bring the clouds down to the ground, displaying changing skyscapes. Five 3m-wide concave mirrors will be placed on the plinth and turned upside down in the hope of bringing visions of the sky down to the ground. Kapoor said he hoped they would "reflect the sky, so that it will become a form of display for the natural phenomenon of rain and clouds and sunshine rather than the political and heroic which is what is going on in the rest of the Square. It will appear almost as if the clouds float across the surface of the mirrors, almost cinematically".

Bob & Roberta Smith FAITES L'ART, PAS LA GUERRE

This illuminated work, to be powered by the elements, is an attempt to rebrand Trafalgar Square as "a beacon of a cultural future rather than a memorial to our military past".

Yinka Shonibare NELSON'S SHIP IN A BOTTLE

JNelson's Ship in a Bottle is a scale replica of HMS Victory in a giant glass bottle. The ship's sails will be produced in richly-coloured textiles, which Shonibare will source from Brixton market. The fabric was inspired by Indonesian batik design, which, by the 1960s, had become symbolic of African identity and independence. Shonibare says his piece will reflect London's multiculturalism.

Tracey Emin SOMETHING FOR THE FUTURE

DA sculpture of four meerkats, reflecting Emin's fascination with the desert mammals' egalitarianism. Emin said "whenever Britain is experiencing sadness or loss (for example, after Princess Diana's funeral), the next TV programme is Meerkats United."

Jeremy Deller THE SPOILS OF WAR (Memorial of an Unknown soldier)

JJeremy Deller's work is a destroyed car which the artist proposes to bring over from Iraq to place on the plinth. By changing its context, the audience may feel re-sensitised to this product of war, said Deller. "It is not an artwork, in the same way a tank in the Imperial War Museum is not an artwork." The symbol of a car was pertinent as it had become a substitute for humans in news coverage, according to the artist. "We never see a blown-up body, we see a blown-up car in the news," he added.

Antony Gormley ONE AND OTHER

Built to be occupied 24 hours a day by members of the public who have volunteered to stand on it for an hour at a time. Over 12 months, 8,760 people are calculated to take part. Gormley said it could be construed as a "soapbox" of sorts and a "place of protest and celebration". Applicants who pass an interview will be winched up to the plinth, with guards preventing them from falling off. Anyone using the opportunity to incite violence or hatred will be hauled off.