SpiderOak » Mac OS application

SpiderOak is a

file synchronization service centered around being a zero knowledge

client only key encryption storage service.

Information about

Only file synchronization service to do zero knowledge highly secure client encryption: Unique selling point
HIghly secure zero knowledge security design: Advantage Reference
Open description of engineering design and security : Advantage Reference
Allows use of two factor authentication: Advantage Reference
Only able to synchronize one folder at a time: Disadvantage
Encryption ensures slower upload and resource use than other non-encrypted sync services like Dropbox: Disadvantage

Spideroak Encryption

Spideroak uses a combination of 2048 bit RSA and 256 bit AES encryption, and strives to create an encryption system that means that even they can't break in. Read more here: - http://spideroak.com/engineering_matters#encryption_specifications

Features

It is also a file versioned storage system.
Maximum file size : Unlimited

Plans

Free Account: Storage : 2 GB Ongoing price : 0 dollars per month Ongoing Price Relative to Storage : 0 dollars per gb month
100 Monthly: Storage : 100 GB Billing Period : Monthly Ongoing price : 10 dollars per month Ongoing Price Relative to Storage : 0.1 dollars per gb month
200 Monthly: Storage : 200 GB Billing Period : Monthly Ongoing price : 10 dollars per month Ongoing Price Relative to Storage : 0.1 dollars per gb month
300 Monthly: Storage : 300 GB Billing Period : Monthly Ongoing price : 30 dollars per month Ongoing Price Relative to Storage : 0.1 dollars per gb month
500 Monthly: Storage : 500 GB Billing Period : Monthly Ongoing price : 50 dollars per month Ongoing Price Relative to Storage : 0.1 dollars per gb month
100 Annual: Storage : 100 GB Billing Period : Annually Ongoing price : 100 dollars per year Ongoing Price Relative to Storage : 0.0833 dollars per gb month
200 Annual: Storage : 200 GB Billing Period : Annually Ongoing price : 200 dollars per year Ongoing Price Relative to Storage : 0.0833 dollars per gb month
300 Annual: Storage : 300 GB Billing Period : Annually Ongoing price : 300 dollars per year Ongoing Price Relative to Storage : 0.0833 dollars per gb month
500 Annual: Storage : 500 GB Billing Period : Annually Ongoing price : 500 dollars per year Ongoing Price Relative to Storage : 0.0833 dollars per gb month

Has clients