Vathara has done it again. Previously she -- I assume "Vathara" is a she -- has crossed Kenshin with, among others, Buffy, SG-1, and, my personal favorites, an RPG called NightLife. Her newest work,
Dragons of Revolution, crosses Rurouni Kenshin with the Temeraire series:
In a world where a British captain is the adopted son of the Emperor, the Opium Wars probably didn't happen... meaning the Revolution may be very, very different.
I was definitely left wanting more.
Note: You don't have to have read Temeraire to enjoy this if you know that dragons exist, there are many breeds, they talk, they are used in warfare and they select a human companion.