image: Wisconsin Dairy Expo

When the annual World Dairy Expo debuted in 1967 in Madison, WI, the paradigm-busting technology was plastic milk containers. While the show's displays of dairy science have evolved dramatically since then, one item has remained constant: the 1-ton globe greeting expo visitors. Consisting of two conjoined silo roofs, the rotating orb is powered by an electrical motor that spins the rear axle of a 1954 Chevrolet pickup truck. The globe was designed by an agriculture journalism professor who painted the continents with sufficient food supplies green, and those with food shortages, orange.