There is a large movement by companies like Apple, MS, Google, DropBox etc, etc to push users to move their files to "the cloud". They claim that this is an excellent idea; you can access your files from anywhere, you can share them and collaborate so easily. Give them your files so they can scan them and sell you ads. Then all your files are sitting on their servers just waiting for some bored teenage wannabe hacker to trip his/her way in and get a looksie at all your files. Yes, they claim it is so secure, that their servers are unpenetrable. How many giant servers have been hacked recently? Sony's playstation network ring a bell?
The upload and download are secure via secure sockets and all that but the real issue is that our files are sitting unencrypted. Sometimes there is even a server side encryption but once hacked that is useless and the FBI as well as the hosting company can still sort through the files as the host applied the encryption. The encryption might as well not be there.
This includes even backup services such as Mozy and Carbonite. I don't see why anyone would use these cloud services.
The only service I have found so far that allows the user to apply a user side encryption, thus making files unviewable unminable on the server, is SpiderOak. I will be upfront, I do not own stock in them nor will I benefit if they succeed. I stumbled onto them and have read reviews and their own propoganda.
I really like the user side encryption that SpiderOak provides. I feel much more comfortable holding the encryption in my hands and knowing that there is also server side encryption so that my data is doubly protected. In my testing, it is easy to share files or perform a backup from any and all of my devices.
SpiderOak, unlike all the competitors I have seen, offer compatibility with Android, iPhone, Blackberry, MS Windows, Apple OS, and even GNU/Linux. It seems that most cloud type software is written for and intended to be used on only one or perhaps two operating systems. They miss their own selling point of freedom and restrict users to their OS of choice.
To sum up: I have subscribed to the SpiderOak service and have used it on multiple devices including but not limited to my Win7 using laptop, a SuSe running desktop, from within Ubuntu running as a guest OS in VirtualBox and an Android using smart phone. It is simple to install, easy to use. Most important, I have control over who, including from the server side, has access to my stored and secured files. SpiderOak is clearly the winner (for now) in the race to the clouds.