Philosophy and Psychology
I'm not sure exactly where I acquired my deep suspicion of philosophers and their product, but it might have been in my first undergraduate Philosophy of Science course. Maybe it was the professor's attitude toward my arguments. Or maybe it was just the fact that my friend the philosophy major not only got the cutest (and smartest) girl in the class but could also routinely beat me at chess.
In any case, I have a antipathy to the notion that thought can get you very far without experiment. Gary Gutting, a philosophy prof at Notre Dame, has a critique of Jonathan Haidt's recent book The Righteous Mind in the NYT. His core argument is that Haidt is too dismissive of Plato's analysis of morality, but an obvious subtext is that philosophy is not irrelevant even in the modern age.
Now it is possible that Haidt, himself a disillusioned former philosophy major, underestimated the subtlety of Plato's argument, but I think his core critique of philosophy is right on: 2000 years of discussion may have produced some insight but no firm conclusions. Haidt, instead, pursues the experimental method, examining how people actually make moral decisions instead of just speculating about how they should.
If you want to tell people how they ought to act, it's useful to first check how they actually do act.