lots of great stuff here! Orwell is neato...Huxley, Upton Sinclair, Howard Zinn, Philip K Dick, Thoreau, Emerson, Herman Hesse, Daniel Quinn (Ishmael one of my favorite books) Terrence McKenna, I dig on some Albert Camus and Sartre, Simone De Beauvoir, Edmund Husserl, Kropotkin, Frans De Waal, Bakunin, Chomsky, Wittgenstein, Kierkegaard, Daniel Dennet, Searle, Schopenhauer, Marx, Hegel, Plato, Gramsci, Adorno....actually just a bunch of philosophers...not worth listing them all.
Lots of great suggestions in here too..I'll have to check some of these out.