Almost 4 years later than this article, I still don't have a good way to store my 1's and 0's.

There's a lot of good software solutions, but you can't find reasonably priced motherboards / sata extension cards with enough sata ports to accommodate a lot of disks.

I need to store between 20 and 30 TB. I have a lot of 2 TB disks that I can't gather in a single machine where everything could be centralized.

Buying 4TB (even worse with 6 or 8 TB) disks is too expensive (let's not forget the cost of redundancy).

So I have a mismatch of (non) "solutions" : hard raid on my desktop, a lot of non redundant external hard drives and a small NAS that backs up the really important stuff. It's not a satisfying solution but I can't resolve myself to throw more money at it : I would need probably more than a month salary (admittedly I don't have a decent salary but still) to build something centralized.