Steampunk Apartment, New York City, United States

In between the historical and fantasy sub-genres of steampunk is a type which takes place in a hypothetical future or a fantasy equivalent of our future where steampunk-style technology and aesthetics have come to dominate. Examples include the anime series Turn A Gundam (1999–2000), Hayao Miyazaki's post-apocalyptic anime Future Boy Conan (1978), and Disney's film Treasure Planet (2002).
Other variants
John Clute and John Grant have introduced the category gaslight romance or gaslamp fantasy. According to them, "steampunk stories are most commonly set in a romanticized, smoky, 19th-century London, as are Gaslight Romances. But the latter category focuses nostalgically on icons from the late years of that century and the early years of the 20th century—on Dracula, Jekyll and Hyde, Jack the Ripper, Sherlock Holmes and even Tarzan—and can normally be understood as combining supernatural fiction and recursive fantasy, though some gaslight romances can be read as fantasies of history." The term steamgoth, coined by author and artist James Richardson-Brown, emphasizes a far darker view of Steampunk's anachronisms.