London's magnificent Tate Modern museum, which was transformed from a power station to a gallery by architecture firm Herzog & de Meuron in 2000, is getting a significant addition, but the new space will not be entirely complete in time for the London Olympics next year. What will be finished is a renovation of "the former power station’s oil tanks, three cavernous subterranean spaces, which Tate Modern said would create 'exciting new spaces for art in the world'." [BBC via UnBeige]