Perhaps best known for Modernity and the Holocaust (1989) and Liquid Modernity (2000), Zygmunt Bauman's sociological and ethical inquiry is immensely wide-ranging but touched by the most basic humanism, a primal one. I'm interested most in his analysis of the outcast, notably Wasted Lives: Modernity and its Outcasts (2004). From class struggles to consumerism, Holocaust to postmodernity and globalization, the circumstances of exclusion and unbelonging have been his foremost concern.
Prolific but never prolix, Helene Cixous' is some of the best theoretico-poietic ecriture, feminine or otherwise. However, ecriture feminine subverts the self-same symbolic mergers. The theories of the Jacques, Derrida and Lacan, among others, are renewed and find rapture in the cursive corpus of Cixous.
Above link to more information on Cixous.
Paul Feyerabend's Against Method (1975) is a must read, one of the most compelling critiques of scientism, more urgent than ever in our super-systematized times, where singular generality meets up with general singularity. Feyerabend's works make Thomas Kuhn's "paradigm shifts" and Michel Foucault's epistemes seem like complicit dawdling. Feyerabend has done more against rationalism as Thomas Szasz has done against psychiatry in such classic works as The Myth of Mental Illness (1960) and The Manufacture of Madness (1970), and this is laudable. In this one, Feyerabend takes it back to ancient Greece, which should be exciting reading for me anyway.
Pretty self-explanatory, but should be very educational.
Above, interesting website, including information and critique of Negri.
I want to add that his wife Catherine is also an accomplished writer. The only English edition of her works is The Image (1956), under the pseudonym of Jean de Berg. Like her husband's films, Radley Metzger's insouciant film version (1976) of her novel is an exercise in patience, but more forgivable. The Image is actually one of the better pieces of pornography by a woman author, but it's not as widely known as Pauline Reage's Story of O (1954), Emmanuelle Arsan's Emmanuelle (1959), or Anais Nin's works, as well as more recently Catherine Breillat's Pornocracy (2001) and Catherine Millet's The Sexual Life of Catherine M. (2002).