Have you looked at SpiderOak? It's a Dropbox competitor and way more secure. Use this link with referral to get more space if you sign up (it's free etc). If you do use that link, also use the promo code "WORLDBACKUPDAY" in addition to going there via the special link and you get more space (6GB instead of 2GB, so a significant improvement!)

I found it through VillainROM's twitteraccount and edited only slightly. It looks great though!