Roger Powell, the creation of Tony Kaye, an artist and film director, announced his nomination for the annual competition outside the Tate Gallery in London yesterday.
Mr Powell was living in a cardboard box near Waterloo station when he was "discovered" by Mr Kaye two years ago. He went on show at the Saatchi Gallery as a "pounds 1,000 work of art" and has been exhibited in San Francisco, Washington and Paris. His price tag has now risen to pounds 4m, according to his T-shirt and placard yesterday.
Mr Kaye, who "designed" him as a comment on homelessness, said yesterday: "I wanted to create a piece of art with a function, and not just something aesthetic."