I have a set of nearly all of them; the only other sets I have are series: Harry Potter, Narnia Chronicles.
Cat's Eye, hands down, is my favorite. It was my screen name on forums for years, but I let it go awhile back. If I ever change my username here, it would be in the running again.
I also love The Blind Assassin. Handmaid's Tale and Oryx and Crake are... not my favorites, but that's because they frighten me too much. I like my science fiction to remain solidly fiction and those two seem eerily plausible in some political and agro-pharmeceutical ways.

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