Years ago (in the era of PATA drives I think?) I had six HDDs in my case. There were room for two or three HDDs or something. Not six. I had some cheap Adaptec raid card.
I made two sheets of 2,5mm/0.10" thick aluminum at my work and put 4 HDDs between them. Then I hanged the whole monster with 3 sheets of rubber (two sheets up, one down, so that those HDDs won't swing/get damage when moving the case) and the another reason was to dampen the spinning/headseeking noise. There were fan or two before them. There were sheets of something self adhesive heavy material in side panels and part of the case. That thing was a back breaker! And quite silent.
If I remember correctly, I had 120GB for OS, one 200GB for workfiles and then 200GB and 500GB mirrors for backups/raid1.
Too bad I don't have pictures of it. There were some other mods with zipties and all. I think it was just before my 2600K-rig, maybe some 2500MHz Athlon or something. Can't remember. I think I had W2K then.
Oh, it was W2K for sure, as I had trouble with Vista Home and recognizing those W2K (pro?) made partitions after full system upgrade.
Lost part of my important backups, since Vista Home didn't support those W2K-made partitions. Had to use hex editor for FAT tables, to change one (1) bit in them! One mirror was readable after that, the another wasn't. Used some third party tool to combine those unrecognizable files, with random names.... What a mess... I bought my first network drive after that. And it failed also...
Long story, still mad about it.
I've made other mods too. Like making Sennheiser HD580 wireless/BT. I should have pictures of it somewhere.... Found one picture. BT receiver is Procaster BT-01 (~20€). Fun project.