I use tarsnap because

- open source
- accepts bitcoins
- Colin Percival of FreeBSD runs it
- other cryptographers recommend it as crypto engineering is solid

This project Storj you use 3rd party tools like pycrypto to encrypt your own files with AES128 in CTR mode, then they just store it in chunks decentralized. I backup TB servers so will be interesting to see how they handle gigantic backups and what that will cost.