Today's article, on oil's price fluctuations over the past 35 years, I found especially good.
My favorite quote is this reminder of the beneficial role that speculators--selfish money-grubbers, all--play in the health of a complex economy:
Of course, all speculators render a useful service by conveying the market’s evaluation of scarcity. Their activity also evens out price movements over time: in the case of oil, they buy now, when prices are lower (in their expectations), in order to sell later, which will bring future prices down. As usual, greed is useful.
Another thing that caught my eye was the graphical representation of the fall of oil's price in 1986, when the OPEC cartel collapsed. It would also seem--at first glance anyway--that they've never really been able to get their act together again.
One of the Notes for the article links to this fascinating page that goes into the details surrounding Julian Simon's bet with Paul Ehrlich. Definitely a fun read. We need more Julian Simons.