Originally I was going to build a NAS, but then I realized it really wasn't what I needed.
Problem: I have a huge full HD movie collection created using MakeMKV which is stored on 2x1TB HDDs. I will need to purchase additional HDDs down the road as my movie collection expand and my desktop can no longer house that my HDDs.
Possible Solution(?): I would like to purchase the parts I need to put all my HDDs in a case, RAID them together, connect it to my desktop through USB 3.0 or Ethernet (desktop is wirelessly connected to internet) and be able to watch my movies and keep expanding my movie collection.
Linux has had it's greatest success in the server space where it's software raid 5 is well regarded for it's performance and superior reliability (compared to hardware raid). Grab pretty much any Linux desktop application and you get that for free. If you browse the Ubuntu or Debian user forums, the home folks using software raid 5 on Atom motherboards (with 4 sata ports) are a satisfied bunch. It is confusing to configure (part of the installation) so my first time I redid the installation which wasted 30 minutes. Obviously a cpu that costs more, burns more electricity, and is stronger also works.