i really like how this looks. only thing is, have you ever worked with plexiglas before? its evil incarnate.
i made my whole case out of plexi a while back
http://www.amdforums.com/showthread....&pagenumber=47
you might want to consider how you are going to make this thing. cutting 120mm wholes in plexiglass is really hard - i cut all the 80mm holes with a hole saw and a drill press, but holesaws dont get much bigger than this. also, cuttting square holes is a HUGE pain. you have to do it with a hacksaw or dremmel, and it takes forever.
ideally you can get all of your pieces laser cut or something, but, if not, it would take a seriously large amount of work to make this thing.
very cool other than that though! after making a cube case, you really start to see the advantages to normal ones...