The only case I have done much to specifically for looks was the Pro/Lan box. But hey if you are gonna take it to LANs then it might as well be nice looking, right? And even that all started because Lian Li put a 80mm blowhole offcenter in the back. When I moved the PSU then it looked really funky so I decided to add a window. Anyway I was reasonably pleased with the look of that case, even if it is a bit over the top.
http://www.procooling.com/~phaestus/.../pc50angle.jpg