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datahoarder
Who are we?
We are digital librarians. Among us are represented the various reasons to keep data -- legal requirements, competitive requirements, uncertainty of permanence of cloud services, distaste for transmitting your data externally (e.g. government or corporate espionage), cultural and familial archivists, internet collapse preppers, and people who do it themselves so they're sure it's done right. Everyone has their reasons for curating the data they have decided to keep (either forever or For A Damn Long Time). Along the way we have sought out like-minded individuals to exchange strategies, war stories, and cautionary tales of failures.
We are one. We are legion. And we're trying really hard not to forget.
-- 5-4-3-2-1-bang from this thread
For drives, Shuckstop has a table of current shuckable drive prices. Shucking is usually the cheapest way to get new drives, you just have to get them out of their external case (or in your case, leave them in and plug them into your pi, ideally with some sort of fan). There's also ServerPartDeals for refurbished enterprise drives.