I took a 1997 gateway 2000 case, sanded it down and painted it a nice glossy black and rebuilt a brand new system inside it. Its very pretty. The only flashy thing about it is in the back where there is an LED fan exausting the hot air. I might put a cold air intake on the side or top, but it will be difficult because the case requires i cut through two different materials (plastic and metal) in order to make a hole. It would be a tough project for a mod newbie, but, with dremel and hand, theres a way.
*edit*
Particle, why not pick up a case of the same flavor as the one you have.
Push the two together and have adhere to each other by either glue or welding. Use the holes on the backplate of your case to run the cables through them, and cut holes through the side of the other case matching those of the backplate. You would need to cut out the backplate on the second case in order to access the drives when you needed to.
You can then fit all your hard drives in that case and run the cables from that case to your main case. That can leave room for an internal Peltier cooling mod and/or any other cool cooling mod you'd like to try.