- why not use subversion version control for private/business document backup
- Quickstart: Versionskontrolle mit Subversion (German)
- svk goes even further sitting on top of subversion (or others): distributed version control incl. offline operation features
- rsnapshot (German): Works on any folder copying only changes, uses hard links, easy to integrate. For remote solution fuse sshfs or avfs (new in Ubuntu Intrepid repos) might help. Or use ssh directly.
- wua.la might be usefull for remote out-of-house storage. It’s a social encrypted distributed “file system”. Local fs integration possible using NFS.
- use gmailfs for remote storage mounted locally using FUSE (also: Using Gmail Filesystem) combined with EncFS (Wikipedia)
- Ubuntu wiki page on backup solutions for Linux
- Duplicity backup Howto
- graphical: Simple Backup Suite
- background on backups on Ubuntu wiki pages
- online solution: Mozy (article could be sponsored, though)