If you mean this...

http://www.arcanewolf.com/trader/tradercommod.html

I have the chart open every time I trade commodities. Its invaluable, and still accurate.

- Nyken

As the others said, it's a valuable resource, but with one caviat. The pit boards don't quite work the way they should. My general rule-of-thumb is never to buy anything unless the one of the other pits is either going fast or nearly out. Even then, unexpected things occur from time to time. Play it safe for awhile until you get a feel for how the prices flucuate and don't trust what the pit runners say.