Here is something what I wanna share. I am using Mozy Home, from Mozy Inc, a EMC company, to backup my local files to a online system. It was quite simple to install and to configure. Every connection is encrypted, the server certificate is checked and you will see an error if something is wrong with the server's certificate, and all your stuff is encrypted on Mozy with a personal key.
After installation there are two processes running on your machine (WinXP), mozybackup.exe and mozystat.exe, each of them are consuming approx. 7 MB of RAM, so not bad at all.
Mozy client is available for most Windows versions and also Mac OSX.
Check it out
For professionals and companies there is also an Mozy Pro version which supports Server OS, Exchange, SQL server etc.