Steampunk
Wikipedia says that steampunk “denotes works set in an era or world where steam power is still widely used — usually the 19th century, and often Victorian era Britain[citation needed] — but with prominent elements of either science fiction or fantasy, such as fictional technological inventions like those found in the works of H. G. Wells and Jules Verne, or real technological developments like the computer occurring at an earlier date.”
(http://en.wikipedia.org/wiki/Steampunk)
The premise of the challenge is simple: right a steampunk story or series.
You can bend the rules of steampunk a little, for example writing a Gaslight Romance or steamgoth (http://en.wikipedia.org/wiki/Steampunk#Other_variants)