For all your encryption needs, I highly recommend
VeraCrypt. The continuation of the highly successful TrueCrypt project, it's free, open-source, and thoroughly tried and tested. The "open-source" part is especially important, and is considered a requirement for an encryption product that's worth your time and trust, as a closed-source product may have backdoors that no one can detect.
Need to store data on the cloud, but worried about others having access to it or the cloud server getting hacked? Simple! Just create an encrypted VeraCrypt container, put all your sensitive data in there, and then store the container file itself in the cloud. No one can access your files without the container passphrase, which only you will know.
That's not a backup. Seen this too many times, people trusting the cloud, then comes a thunderstorm and that specific cloud where your goodies were is blown away (with or without encryption). Think decentralization!
I used duplicity with free protonmail accounts to backup some important data offsite (additionally to local backups).
I agree thet Veracrypt looks mature, unlike i.e. encfs based things that shouldn't be trusted with important data as its not good enough for that. But it's a nice overview that VB1001 posted, thanks.
A local folder that syncs with a cloud service does not have this problem. Dropbox for example.
That's still not a backup, the article VB1001 quoted talks about backing up to the cloud, not just having a synch'd copy there.
(I know backing up is for coward pussies but still I beg to differ)Well, the very definition of backup is that you have some data stored locally, and you perform a backup by copying the data somewhere else, at regular intervals (or in real-time), so that if something happens to the local data, you have the backup version to restore. So, in that sense, you'll always have a local copy, even if the cloud server gets hacked, or loses the data, or gets obliterated by aliens, etc.
The main point I was trying to make, was that strong encryption tools like VeraCrypt can protect you from someone on the cloud side looking/stealing/using your data. To them, they are just a bunch of useless random numbers. The chances of Google or Dropbox losing your data are very remote IMHO, as their data farms are backed up continuously and in a highly robust, professional way, so they can restore a very recent version of the data if need be. OTOH, my daily backups can fuck up much easier by a mistake or h/w failure.
Generally I'm against anything cloud-based, the only reason being the lack of privacy. With tools like VeraCrypt, the privacy issue is resolved, so one can benefit from the positive side of the cloud.
Having said all of the above, I don't even think about putting my cold storage private keys / recovery seed anywhere near a PC or other online electronic device. It is backed up safely in several places, physically far away from each other, and in non-electronic form. But the beauty of the recovery seed is that you only need to do this once (storing in several places). No matter what happens inside your wallet, whatever you deposit/withdraw, etc., the seed is always valid and always stays the same, no need to update it. It's not the same with actual data, where you need to regularly update the backups when you make changes to the data. That's where the cloud comes in, and with tools like VeraCrypt it saves you a whole lot of trouble in maintaining your privacy while enjoying its benefits. It kind of like Bitcoin, but with data.
Edit: ...and I wouldn't go anywhere near an online service like freebitco.in, trusting my coins to someone I don't know for a mere 4% gain... No way!