Kirsty Young's castaway is Mary Portas. She's made an art-form out of turning heads, and her galleries have been the enormous plate-glass windows of Harrods, Topshop and Harvey Nichols. These days she brings retail therapy to small traders, helping them to hold their own against the high street's big names. Record: Casta Diva from Norma Book: The works of Rumi, Persian poet and philosopher Luxury: 'A set of different fragrances from the people I love'.