About six years ago I had a hard drive fail at home and I lost a lot of stuff.  I was embarrassed as I was a network administrator for our local bank and got paid to make sure those types of things didn't happen.  From that time on I started subscribing to Mozy which has been super reliable for us.  We have not had to rely on it yet but I check the backup status regularly as I don't want to go through the hassle of recreating the data again.

One thing I learned while in the IT business was that a truly good backup system is robust.  In an ideal situation every place data is stored it would be duplicated.  I'd love to run a RAID 10 system in all my workstations and also have a backup system that stored a backup locally (RAIDed again) and offsite.  For most people/business this is overkill and overly expensive.

Now that Google Drive has become reasonable in price I may consider revamping my setup but I really do like the convenience of Mozy.  Carbonite is also good as are others I'm sure.