Truly works of art! Since they are "custom-made" by this company only and out of expensive aluminum, I believe the price. They are low volume so they have to have high prices to cover their fixed costs.
$500 is too much for me to pay, but at least you can rest assured that this case won't really go obsolete for at least 3-4 years unless the ATX standard changes radically. Unlike a GF3, this $500 outlay will last quite a bit longer.