Ask HN: What is cheapset method of data storage?
What is cheapest message of data storage per gigabyte?
To take some extremes: data you read and change very frequently might be cheapest stored on RAM disks (backed by SSDs) - CPU time is heat and electricity, and in a datacenter that can become very expensive.
a small amount of data you can afford to read very slowly if/when you need it could be cheaply stored in Amazon's Glacier service.
Data where redundancy and ease of management are unimportant can be happily stored on 2TB commodity hard drives which you can get readily for $40/TB.
If it's the right amount, time and place, there're freebie USB pendrives, at a cost of ~$0/MB if you have one lying around.
So, what's your use case? That will lead you to your storage.
How important is the data?
What level of redundancy do you need?
How much data is there?
How frequently will you be writing new data into the storage set?