2nd millennium mechanical storage? How about magnetic tape and paper punch cards?
The same amount in SSDs, the cheapest and worst type, would be 7-8x more and getting them to run in the form I need would probably cost another $1-2000 on top for a rig to operate them. It's all backed up so it don't matter if it croaks but I've only ever had one mechanical HDD fail and that was after 12 years. I'll take them odds.
I'll confess to a little hyperbole.
If you don't move your HDDs, mount them with rubber grommets and use an UPS, they should last a long time. You're lucky to have avoided failure that long though. Of course thorough backups are a must but some sort of redundancy is a good idea... RAID-5?
The days of RAID-0 are long gone. Speaking of HDD failure, my first RAID-0 array was 4 IBM 75GXP "Deathstars". I was so proud of my blazing fast third-of-a-terabyte C: drive until I started reading stories about those HDDs failing left and right. Never did have one fail though until I replaced the array with Raptors. Ended up using the IBMs to upgrade other people's old machines with <10GB HDDs. Never heard of one of them failing either.
Once I replaced my Raptors with Vertex, I never looked back. Pissed me off to have the array bottlenecked by the southbridge but soon fixed that with a PCIe RAID card. Next step was the OCZ PCIe Revodrive series and now of course it's NVMe.
Gotta move with the times.
Still have a drawer full of old HDDs in the 100GB-4TB range but they're pretty much just archives and backup. Now I have a couple of 2TB SSDs for onboard data storage (besides the C: drive) in my main PC and a few more in external enclosures in my laptop bag. Every now and then I haul out the old HDDs and copy over a few terabytes of movies onto the externals. That's the big problem now... how long it takes to copy multiple terabytes via USB3. eSATA ain't much better.
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P.S. All this talk of storage has me thinking that we all owe a little thanks to Joe Breher for his work in making these storage technologies possible. Many people here see him as an argumentative pro-BSV "troll". He's a lot more than that.
Thanks Joe.