Gilles Deleuze and Felix Guattari - A Thousand Plateaus: Capitalism and Schizophrenia (Volume 2)
The book tries to establish a system of political, psychological and semiotic descriptions, always as a mode of resistance to all kinds of fascism, and D & G take the conflation of those levels as a given. Not just in the world of theory but also in how you think, and that's why it's written in such a particularly dense way. It tries very hard to be nonoppressive, and generous too, but for lots of people it can be a frustrating adjustment, accustomed as we are to writing that tries to be as flat and simple as possible. This book reads the way it thinks, and these two definitely prefer finesse to simplicity. Once you get into it, you may find that it's the best thing you've read for as long as you can remember. Or, at least that it makes you think in ways you don't while reading other books.