I've thought about this type of servece recently because CD's and DVD's are just not giving me the confidence of data centers. They know how to not lose digital data like pictures, movies and other stuff I would just HATE to lose. I had a back up harddrive and put too much trust in it. Although the data was not that important, when it broke, I was pretty pissed not to get the data back.
I have made big changes to my website and thus, checked how it looked frequently. Google's Adsense placed a Picture Ad of Mozy on my homepage and it seemed pretty interesting. Mozy offers an unlimited back up account for $4.95 a month. When I saw it's an EMC company, I knew the expertise is there as well. I actually hold a few EMC stocks so I know what EMC is about.
The only thing is the first upload. It's taking more than a month now to upload the data. But so what. Almost 1 % done now... LOL