I used to buy PC components separately and build my own, but since the insane hardware rush came to an end about ten years ago, rather than the constant upgrade treadmill, I tend to just buy a brand new system in total every ~6 years, maybe with a mini-upgrade (GFX, RAM) part-way through if absolutely needed.
So, after many years of pretty much the same sort of boring, plain tower case, the last system I got which met the approximate specs at a reasonable price came with a case with a totally unnecessary glass side and a load of multicoloured LEDs blasting out patterns over the wall.
Well, okay. It's not totally horrible. I am however completely baffled at why I or anyone else should give a shit. It's probably so cheap compared to everything else it makes no significant cost difference, but I just don't get it. I kind of think computers are a bit like people in the sense that what matters is what they do, not what they look like.