Incarceron is one of the more wildly imaginative books I've read in a while. Forests made out of metal, airships inside, and animals that might have a bit wiring weaved into their veins. The narrative winds between a boy trapped inside a futuristic, living prison and a girl on the outside, in a faux 17th century world, trying to get him out. The outside world has outlawed technology and everyone is forced to live "in period", though occasionally people cheat, which makes for some intersting scenes...like a scullery maid secretly whipping out a laser wand to get rid of her wrinkles... Try this for a fresh, original fantasy.