Disc changing robot
Looking into tape drives they really don't make sense. The tapes are very expensive, the drives are very expensive, and the cost per GB just isn't good enough at the consumer level. I really don't understand why anyone would want to start using tape drives. Maybe they're getting discounts on large orders?
The cost for blueray discs however looks a lot better. I can get 50x25GB bd-r discs for $36 canadian from amazon. That's roughly 0.0288 per GB. At the time of this writing the cheapest hard drives (on amazon) is 0.019 per GB, quite a bit cheaper. Still that's an external hard drive that requires you to "shuck" the case. I'm hopeful that there's room for bd-r prices to go down, especially if you're ordering in bulk. Optical media also purportedly lasts longer, especially archival grade discs.
I'm honestly pretty surprised optical discs can't compete with hard drives on price-per-GB, at least on the consumer level. I imagine they'd be a lot cheaper if you ordered in bulk... Something to look in to.
One thing to note is that modern blueray players tend to be compatible with everything back to CDs. This means you've been able to buy a CD reader for ~30 years! Sony's "optical disc archiving" shows that there's still room for optical discs to grow, for storage density to increase, etc.
Looking at it more in-depth, I think that the price of bd-r discs makes this a lot more niche than I had hoped. If the price-per GB could drop significantly I think a disc-changing robot would be economical. I had imagined using pick-and-place style vacuum pumps to load discs. Something that fits in a rack-mountable unit and that could store between 20 and 80 TB depending on the discs. Unfortunatly that would be a lot more expensive than just buying a bunch of hard drives and putting them on a shelf when they're not in use.
That's not what this page ended up being about though.
I doubt there's a big enough market willing to pay a premium in not only cost but also access time, just to get a media that will last a few decades (1000 years? todo, look into m-disks claims). Those kinds of organizations will probably just shift media as new technology becomes available.
Sony's optical disc archiving system does look pretty cool though.
