The only one I can really recommend is SpiderOak, due to their zero-knowledge policy on what users upload. Everything is encrypted with your password, and if you lose that, you're SOL. They have no way of seeing what you've uploaded, so they're just providing you some drive space. It's a wonderful service altogether.
If you would like to help me out and use my referral link (so you and I get some extra free GBs), it's https://spideroak.com/download/referral/049cbbf6bc2c2df3b005...