After hearing about programs like PRISM, I don't trust cloud storage very much to backup my computer files. I'd like to know a way, the best way, to backup about 5-10GB of storage and ensure that I am the only one that will ever be able to access it. This should be "off-site", meaning not in the same room or building with my computer, and free or a pay-once model would be nice.
Things I've already found or thought about:
1) https://prism-break.org - A neat website with all sorts of ways to keep your information private from PRISM and similar programs, though their mentions of cloud storage seem to mostly show protocols supporting some type of blockchain or Tor cloud storage services without any viable providers of it yet (most/all are in beta).
Put my data on a USB drive and carry it around with me. However, if that drive is lost whomever finds/steals it will have plenty of time to try and crack any encryption I have on it (as encryption is being broken all the time, and newer methods are used) so then they will have my files. Are self destructing drives a thing? How would that even work without it accessing the internet? I could put all my data on a micro SD card and surgically plant it into my skin, but I don't think I'd ever want to go that far. And it will be a pain if I want to update my backup files.
Put the files on my phone. Cell phones might have better encryption than what I could have on a USB drive, but since I use Android, which I don't exactly trust (i.e. owned by Google), my files could be accessed when it's connected to the web or a certain app that snoops around the directories.
Use a physical public storage unit, or even a rented bank deposit box, to store a hard disk drive. In the long run this will cost too much $, and if I can't afford to pay it who knows what will happen to my stored drive, and then if I'm trying to recover my files and can't get the drive I could lose my data forever.
TL;DR Which method do you think is the safest and what is your reasoning? Which cloud storage provider do trust the most that is safe from government or attackers? Is it best to wait for blockchain cloud storage to be a thing? Do you have any other ideas?