Sometimes architectural activists are successful in their attempts to save buildings that they find to be iconic in design or history. Case in point, the "flying saucer" in St. Louis was slated for destruction but through perseverance and some help from Starbucks, the structure will be around for at least a few more years.

The greenest building is the one already standing, even if it is a former gas station. In St. Louis, preservationists are celebrating the adaptive reuse of a landmark gas station known as the flying saucer into a Starbucks. According to Michael Allen in Next American City,

   "The gas station, which later became a Del Taco restaurant, essentially consists of four tapered columns supporting a hyperbolic paraboloid, or tapered round roof — hence the nickname “flying saucer.” Richard Henmi served as project architect on the saucer for the firm Schwarz & Van Hoefen, and the gas station was completed in 1967. Now retired, Henmi was able to fight for its preservation and see its adaptive reuse."

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