For a man who has a lot on his plate, 55-year-old Peter Gabriel looks remarkably relaxed. He veritably twinkles when he talks about the Africa Calling project. On Saturday, to run at the same time as the Live8 concerts, Gabriel, Midge Ure, Youssou N'Dour and Womad will put on an event at Cornwall's Eden Project to rival - "Ahem, complement," says Gabriel - the main event in London.