A while back, a friend of mine who's a filmmaker, asked if I had any ideas on how to do fairly big storage without a huge initial cost. Performance is not a big issue, but reasonable redundancy is.
So I started thinking about using Linux software raid to build a RAID 60 of 2.5" disks over USB3. USB3 hubs are cheap, USB3 SATA controllers are cheap and 2.5" SATA disks are cheap.
Is there any reason why I couldn't add a hundred USB disks, perhaps in groups of five in md RAID6 and then striping them to get a very big RAID60?