Under this header you can therefore find any object that you not find under the other categories. Very high buildings are built with steel, today often with a concrete core. Transportation terminals and arenas demand large free areas and are therefore almost always built with a steel framing system.
For structures where you want much light flow into the building like greenhouses, air terminals, glass coverings and shopping malls the combination of steel and glass is unbeatable. Sports arenas are today often given a large spanning roof that almost always is carried by some extraordinary steel structure. Also the grandstands often consist of a steel framed structure.
Other common but a bit forgotten structure types are the masts and towers. These are most efficiently built with steel. Steel structures exist wherever you turn.