Six new artworks proposed for the fourth plinth in Trafalgar Square have been unveiled.
Among those vying for the position is a burnt-out car from Iraq and a replica of Nelson's ship in a glass bottle.
In 2003, London mayor Ken Livingstone backed plans for the plinth to be used as an ever-changing artwork display.
Thomas Schutte's Model for a Hotel 2007 - an eight-ton, 16ft (5m) sculpture made from coloured glass - currently occupies the north-west corner spot.
As part of a public consultation, people will be asked which one of the artists' models they prefer and why.
The exhibiting artists are Jeremy Deller, Tracey Emin, Antony Gormley, Anish Kapoor, Yinka Shonibare and Bob and Roberta Smith.
Bob and Roberta Smith's creation is a wind and solar-powered structure.
Mr Smith said: "The sign says make art not war... in French, powered by the wind and the sun.
"The plinth has no power and you can't drill into it so I wanted to battle with those things and make something very tall that had a light show on it. We have done all the science on it and it will work."
A permanent King William IV statue was intended for the fourth plinth but a lack of funds meant it remained empty.
Experts gave up trying to find a permanent fixture for it in the early 1990s, because no-one could agree on what was appropriate.
The current sculpture, installed in November last year, replaced Marc Quinn's Alison Lapper Pregnant.
Models of the proposed works by the six shortlisted artists will be on show at the National Gallery from Tuesday until 30 March and the winner will be announced in May.
The artwork will be installed in 2009. Here are the shortlisted pieces:
- Jeremy Deller's The Spoils of War depicts the remains of a civilian vehicle destroyed in Iraq
- Anish Kapoor's Sky Plinth is five concave mirrors cantilevering off the plinth "displaying" the clouds
- Tracey Emin said her sculpture of a small group of meerkats symbolises unity and safety
- Yinka Shonibare's sculpture is a scale replica of Nelson's ship, HMS Victory, in a giant glass bottle
- Anthony Gormley wants to ask members of the public to stand on the plinth for an hour each to occupy it for constantly for 12 months
- Bob and Roberta Smith's wind and solar-powered creation sends the message, make art not war