Fourth Plinth in London's Trafalgar Square

It's pity to have an empty plinth. What's a city to do with a monument base that is missing its monument? The Fourth Plinth in the northwest corner of Trafalgar Square in London was planned to display an equestrian statue, however due to insufficient funds the statue was never completed and the base stood empty. In 1998 – over one hundred and fifty years later – the Royal Society for the Encouragement of Arts, Manufactures and Commerce commissioned three contemporary sculptures to be displayed temporarily on the plinth. A plinth is the base or platform upon which a column, statue or monument rests. There is a plinth at each of the four corners of the city's square. The two southern plinths carry sculptures of Henry Havelock and Charles James Napier and the northeastern plinth has an equestrian statue of George IV. A call was put out to artists to suggest ideas for a sculpture or statue for the plinth. Naturally, a wide variety of ideas were submitted. I wonder if any souvenir replicas were made of the ever-changing plinth topper designs?