I took the day on Monday, and PrairieMod had a nice catch — this page from the June 1930 edition of Modern Mechanics showing a proposed Frank Lloyd Wright skyscraper for New York City. The building was to be built of concrete and glass with no structural steel.
One of the unusual features of this building is that no structural steel will be used anywhere in the glass house. In detailing his idea, Mr. Wright pointed out that he plans to build this all-glass tower to a height of 18 stories and set a two-story penthouse on top of it for his own personal use. The walls of the building will be made of clear, heavy plate glass and the floors will be of concrete inlaid with a rubber composition to deaden noises. For decorative purposes, balconies and parapets, Mr. Wright proposes to use copper.
From the same issue: a giant bus with a landing strip and swimming pool. Admittedly unrelated, but cool.