Depends what exactly are you wanting the back-ups for? If it's just to secure your own data on one computer, or a couple computers on the same network then don't bother with cloud services. If you're needing a certain set of files synced between multiple computers on multiple networks then yes cloud services could be of use to you.
My $0.02 : Don't use cloud services for any sensitive information. Putting them on a random server on the internet, within reach of who knows how many people, nothing's a secret. Your files are only as safe as the protection they put between them and everyone else. Case and point: If at all possible just setup a couple externals on the computers, or networks, in question and run back-ups straight to them, then pick and pull what you need.