Foucault has been one of my number one guys for a long time. His life and work are absolutely facinating. I recommend Discipline & Punish: The Birth of the Prison as his most accessible work. His History of Sexuality is a little more difficult. But it does explain fairly clearly exactly why everything you think you know about sex is wrong. The Order of Things: An Archaeology of the Human Sciences, which explains absoluetly everything, reads like backwards upside-down Chinesse toaster blueprints. I do not recommend it because I have no idea what he is talking about.