I have been searching for poster-sized prints of Nancy Elkholm Burket's illustrations from James and the Giant Peach. Hers were in the version of the book I had as a child, and I am hoping to have one at some point to decorate the kiddo's room. I loved how they fit in with the fantastic nature of the story, like a half-dream.
(The following one is actually my favorite, and I did make a copy to hang on my wall when I was younger. I wanted to get lost in those clouds.)