During its often-troubled nine-year history, London's Design Museum has staged nothing better than its new exhibition on Charles and Ray Eames. 'This is the show I always wanted to see here,' said Sir Terence Conran in his opening speech. A sharp-suited Peter Smithson, longtime friend and admirer of the Eames, sported a 1960s shirt for the occasion. Proof of the Eames' democratic appeal was the presence of Tony Benn. 'Charles loved to talk politics,' he said, 'and I learnt everything about design.'