The Turin Motor Show is traditionally the place where the top European car-designers exhibit their latest fantastic creations. William Woollard examines tomorrow's shapes and reports on what the manufacturers are offering today. Chris Goffey visits the Pininfarina Museum and discovers 'what might have been' for some of Britain's most popular cars. Frank Page road tests the latest executive model from Fiat, the Croma Turbo, ie, and sees how they put fire into the Panda 4x4.