Are you referring to the special chrome plating? That was DreamPC's special "touch" to the case to give it that unique look.
"The Dream Machine is all about going the extra mile - in parts and aesthetics. To give HP's Blackbird case our own unique stamp, we had the whole thing nickel plated."
"The cost of having an entire rig plated runs from $5,000 to $10,000, depending on the plating metal."
The article said the case would be available for purchase by itself, but as I recall, the price was astronomical for a case (greater than $1k). I will find the sentence and post it. Also, as I recall, someone here on the forums actually worked on the chrome plating.
According to the article HP is selling a select few of them beginning on September 1st. I believe the price is $1000. It's first come first serve, and when they're gone they're gone. The number to order one is in the article.
Exact quote: "HP will sell 25 of it's Blackbird cases on a first come, first serve basis beginning September 1. The cost is $1,00 (plus tax and shipping). To order, call 877-776-4752."