I take periodic Acronis images of my music drive, and have backed up files and whatnot using various softwares.  Basically, these backup schemes like putting every file in a combo backup file, which risks that large backup file getting one corruption and you lose everything.  Or the software that made the backup doesn't work anymore, or you changed operating system and the files won't open.  Hooray!  There is this program out there that someone at Microsoft made called Richcopy for IT professionals.  Basically what it does is make a copy of the files you want to save.  It just copies the files .. to in my case a USB 2T external drive.  So if you lose something, you just go navigate around in the copy and there it is. 
 
It also compares your set of files to the copy of files on the external drive, and copies all the new and changed stuff ONLY over to backup copy.  Sweet.  So it makes a backup quickly, since once you've got the great big back up of ALL the stuff you don't want to lose, making further backups only deals with a subset of files you've messed with. 
 
I put this command inside a .bat file.  so I can run a backup everytime I quit a session.
 
"C:\Program Files\Microsoft Rich Tools\RichCopy 4.0\Richcopy.exe"   "C:\Documents and Settings\timeking\My Documents"  "E:\RichCopy" /FSD /TSD /TSU /NE /PRP /SZ /V /TD 10
 
which tells richcopy that the folder I want to keep backed up is "My Documents" where all my Sonar projects and audio resides, and maintain a current copy of all those files over in my E drive (my 2T USB drive) inside a folder called 'RichCopy'.  You could call it anything.  I think this is sweet.  And its free.  And it will work under any operating system because it doesn't do anything except copy.  NOTE:  If you try to backup your whole operating system drive, a lot of the files won't copy because they are "in use".  That is why I still do an Acronis image.

You can always use Microsoft's SyncToy.

If you have any reservations about losing your backups, then you should backup your backups, and if you are worried that your house might burn down, do a backup on the internet or store or leave backup hard drives around your girlfriend's house. If you are worried that the earth may destroyed you could organise the backup be sent into space, or paste a binary image into the coffeehouse forums... Well you get the idea :)
 
At the end of the day imaging is here to stay as it is extremely comprehensive and now used in running virtual operating systems (on many servers). Mirrored drives everywhere is also a great idea.
 
Cheers...

It's easy to make data backups. If you care about the time you put in to the music, might as well back it up - a lot.
 
What's not easy is to make a replica of your whole environment in case something unexpected sneaks in and you can't figure out why it no longer works, when just a week ago everything was working great.
 
Acronis, which allows you to conveniently back up everything across all your drives, is designed to do just that.
 
Acronis has saved my bacon several times.  I've had a few times something go wrong with my system.  Whether it was an automatic Windows update that went wrong, or whether I either installed or uninstalled something and the result was that something wasn't correctable, after I got into the jam I was able to click one button on Acronis and it restored everything back to the way it was.  Amazingly convenient.  If I didn't have that capability I would have had to wipe my drive and start over with install after install of programs.
 
I understand the concern about "what if that one Acronis backup file is messed up?" from the OP.  My answer is to use Acronis and backup on more than one drive.  You don't have to do that each time, but can rotate your backups on different drives on some sort of rotation schedule.  Then you'll be covered from even the worst of disasters.

You can do a fair good job too - in Win 7 at least - with Microsoft's own built-in backup. It's certainly simplistic and doesn't have near the options that Acronis does, but it does image backups - and the image backups are incremental too. Coupled with Gobbler - I feel very safe. (Lord knows, I've lost entire drives.. school of hard knocks, etc.)
 
 
I was (and still am) a fan of Retrospect - but I was using my PC as host for the whole house. (Retrospect supports clients as well as the machine it's loaded on..) I decided to get it off my machine because I didn't like it running when I was running Sonar. I could of had it run backups in the wee hours, but folks here simply turn off there PC's without thinking and it's just too big of a job to train them otherwise. So...I had Retrospect running in 'opportunistic' mode for those clients and whaddya know - they'd boot up while I was in the middle of a song, and Retrospect was off to the races...  (I made one of those clients the blasted host... and decided to do backups for the DAW (my PC) locally using Backup.
 
It's working quite well...
 
2 cents...

I always keep 3 copies of each of my projects. Each are stored on a different drive and one is stored off site, in case of fire or theft.  I also store each back up as a CWP with Per Project Audio Files. I do not use CWB for storing!!
 
CJ