If Rowland made PC cases.....

There are a whole range of companies that make media PC cases... Try googling Ahanix, Antec. These puppies typically aren't cheap, but do offer a good range of in/out options and--most importantly--are typically configured to be *very* quiet...

My favorite tho', is the pre-made Niveus Denalis...

Here's a link to some I just pulled up--can't vouch for the vendor, but there are some pics:

http://www.pctoyland.com/sub_ComputerCases.htm

Hmm... The Ahanix link there didn't work. Take a look at this:

http://www.ahanix.com/dvine5.html

The Silverstone cases look pretty nice too.

In addition to the case being attractive amongst your equipment, if that is where you will place it, sooner or later your most important consideration will become noise from the various fans in virtually any self-assembled PC.
In order to have a very quiet case, my experience ultimately led me to look for something with large case fans that can rotate at low speeds. I have given up the looks of two Silverstone cases (and they can be very good looking even amongst Levinson equipment) to go to a tower with 120 mm fans with speed controls. The case I selected was a Tsunami, looking somewhat like the vertical Theta power amps, but without the machined surfaces. Available in both black and silver.

I agree with pc noise being a problem in the home audio setup, which is why I like this site:

http://www.endpcnoise.com/

They have a totally silent machine that cools with no moving parts in a soundproof case, nice! It kinda looks like a tower amp on wheels:

http://www.endpcnoise.com/cgi-bin/e/tnn_p4PC.html?id=N2kDiPQo

Not sure if you've already chosen a case, but I just saw this review up on Tomshardware

http://www.tomshardware.com/howto/20050614/index.html