What really makes me laugh with all these post structuralists is that they try to destabilise all discourse as meaningless but in doing so imply either that they themselves are meaningless,or that they have the 'key' to the truth. In other words they have shifted the power discourse from the dominant accepted meanings to themselves!
Most great philosphers are excellent at critique and deconstruction but almost always create a system just as opressive or marginally less so as an alternative. The truest thing any philosopher ever said was Kierkeegard: 'Subjectivity is truth'. But then he went and mucked up all his good work by saying true subjectivity was in fact his version of christian theology.