Howl's Moving Castle
(sequel: Castle in the Air and the House of Many Ways)
Full confession: I have not read the House of Many Way and have read Castle in the Air only about two times
But Howl's Moving Castle, that I have read many many times, in addition to owning the movie which is very different from the book, but is still brilliant. I digress. I was always drawn to stories of magic and magicians which might explain a lot of Wynne Jones' book and I love the story of the magician Howl and his demon and poor Sophia who is under a curse by the Witch of the Waste that has turned her old.
A Tale of Time City
A science fiction tale of Time City, a city which exists outside of history and whose purpose is to keep history on course. Vivian is kidnapped by two boys from Time City thinking she is the source of problems that history has been having. I liked how the technology is described and the image of the clothes the denizens of Time City has stuck with me. It's amazing because the computer pads the children use are actually quite a bit like an iPad. There is also a quest aspect in the story and I credit this story with my love of quest/puzzle stories.
The Chrestomanci Series
The Lives of Christopher Chant
The Magicians of Caprona
There are other books in the Chrestomanci series, but the ones listed above are the only ones I have actually read. These are fun books dealing with orphans, multi-dimensions, magic, and love. I could not get enough of Charmed Life and The Lives of Christopher Chant and I loved figuring out the mythology of the stories. I actually read them out of order the first time I read them, but it was amazing to me when I figured out that this Chrestomanci was actually Christopher or Cat.
The tale of the Dog Star who is sent to Earth in the incarnation of a dog after being convicted of murdering a fellow celestial body. This book always touch me, partly because I am a dog lover and I love the idea of something being bigger than it really is.