Wired's Raw File blog has a beautiful photo-gallery of the magnificent model railroad spread at the Walnut Creek Model Railroad Society, under construction since 1974: "The society's control systems are a steampunk fantasy: a roomful of vintage 1930s magnetic relays once used to route phone calls, clacking like mechanical dominoes with every move the amateur engineers make. A full complement of 30 members can run 10 individual trains simultaneously on the layout, though only a dozen or so are required for basic operation."