In 2011 I signed up for CrashPlan and I’ve been a big advocate ever since. It’s a fantastic cloud backup service. You just install it on your machine, pay a small annual fee, tell it what folders to watch and you’re protected! There’s no limit on how much data you can upload. I have 3.9TB uploaded now!
As the size of my backups have increased, there have been two times when the app has stopped working. Both times were because the app was running out of memory to look at all the files and figure out what had changed. There’s an easy fix which is well-documented on the CrashPlan site. You just edit an INI file and restart the service.
If you’re not doing any kind off site backup yet, go to crashplan.com and sign up. It’s a tiny amount of money to be protected against all kinds of problems and data loss disasters.