[Bluerise]

Cyphertite[1] works very will for encrypted backups.

It splits your data in chunks, encrypts them on the fly while sending them to the cloud. It doesn't use much space, apart from a little metadata, and you don't have to worry about the NSA, as the encryption keys are only on your local machine.

[1] https://www.cyphertite.com

[cortesoft]

If the encryption keys are only on your local machine, how do you recover the data when you lose your local machine?

[Bluerise]

You should print it or write it down and store it in a secure place.

[aestra]

Hopefully in multiple places, in case of fire!!

[blueskin_]

This.

Safety deposit box at a bank, trusted non-local family member's house, and trusted international (preferably different continent) friend's house should be enough for most cases.