Talking of the Bilbao Guggenheim, two jokers (British) were caught last week trying to strip off part of its dazzling titanium roof. The two were 22-year-olds and it was the early hours of Sunday morning, so one might speculate about the immediate cause of this jaunt. They were quickly arrested and released on bail. Perhaps they thought it was lead, or aluminium. Both have high residual value, but titanium does not. The 33,000 sheets at Bilbao weighed about 132,300 kilos and cost about £15 per kilo. Its scrap value,alas, is about 60p per kilo - or the price of a litre of Spanish lager.