[Quiet Man Cometh]

I might object if one took a very old and very valuable manuscript to do it, but on the whole, nah. I like to make things myself and book art, while not something I've done, is something I've thought about. I've seem some lovely greeting cards made from book excerpts and stamps, among other things. I certainly wouldn't call it offensive either, unless the author of the book in question happened to have a particular gripe with it. It's the same thing when one cuts out and glues the pages to make a book-box.