I use a few old 3.5" HDDs for backups, but got tired of them laying around loose, so I designed this rack for stacking three of them at a time.
Though it is not a remix, I want to give credit to Pmoshbr's thing here: https://www.thingiverse.com/thing:3082230 for giving me the basic idea, but I designed my version from scratch.

My prototype in the photo looks quite rough as I was printing it with 0.3 layers and at 90 mm/s. If you have more time and patience than me, I would recommend 0.2 layers and slower speed to make it look better. For me, function goes before look.

I am thinking about creating a 2 HDD and 4 HDD version, but with 3 old HDDs it is already very heavy, so 4 might be a little unhandy.