Palmolive Building, Chicago

Once the abode of the Colgate-Palmolive-Peet Corporation, the edifice sprang to life in 1929 courtesy of the wizards at Holabird & Root. These design gurus were renowned for birthing various architectural styles – think Chicago School, Art Deco, Modern Architecture, and even Sustainable Architecture. And guess what category the Palmolive Building fits into? Yep, it's right there in the Art Deco realm.

Back in the day, it was hailed as a "monument to cleanliness", marking a historic first by becoming the first skyscraper to boldly venture far from the Loop, gallantly standing its ground at the northern end of Michigan Avenue. In fact, it was one of the country's pioneering "set-back" Art Deco skyscrapers, setting a trend that would soon become all the rage. "Set-back" designs gained popularity thanks to zoning laws and the sketches of New York architect Hugh Ferns, transforming this structure into a formidable sculptural masterpiece.

Oh, but there's more to the story – the Palmolive Building didn't just light up the skyline; it literally beamed as a navigational beacon from its pinnacle between 1930 and 1931. The shining star, known as the Lindbergh Beacon, perched atop a towering 97-foot spire, was the brainchild of Elmer Sperry, the gyroscopic genius. Sperry's gift to the City of Chicago, the beacon illuminated the way for all; however, in 1981, it met its match – private windows were getting a tad too personal with its glow. But fear not, in 2007, it made a triumphant return, its beam now arcing over Lake Michigan, keeping the peace with no more window-worries.