AWS Glacier

Glacier is an extremely low-cost storage service that provides secure and durable storage for data archiving and backup. In order to keep costs low, Amazon Glacier is optimized for data that is infrequently accessed and for which retrieval times of several hours are suitable. With Amazon Glacier, customers can reliably store large or small amounts of data for as little as $0.01 per gigabyte per month, a significant savings compared to on-premises solutions.

http://aws.amazon.com/glacier/

FAQs
http://aws.amazon.com/glacier/faqs/

glaciercmd
Linux command-line app for accessing Amazon Glacier secure slow storage.

http://blog.nekoconeko.nl/blog/2012/08/25/Amazon-Glacier.html

https://github.com/LordGaav/glaciercmd