I don't see a case in the sig... from my experience the case is the key. You can make some bad cases look great with patience though. Other cases need to be modded some. I would do a google for cable management and have a look at some of the threads on other forums too. Have a look in the Worklogs here.
Me, I went to Princess Auto and bought some black zip ties, tie anchors and some black split loom. I didn't use much of the split loom, but the zip ties come in handiest for cleaning up the cables. The tie anchors are not that great, the ones I got, as the adhesive doesn't stick for very long in the warm environment of the case. It was worth a shot though.
That mass of cables, I got rid of it by getting a modular PSU

Yeah, I know that is no help, but I couldn't resist.