Originally posted by: drag
Try looking at rsync.
It's a very advanced tool usefull for synchronizing files across insecure and slow internet links. It basicly does a 'running checksum' on files to compare any changes between them and then only transfers the changes between the machines to match the files. That way you don't waste bandwidth and it's done as quickly as possible. Works over ssh (that's configurable) and is secure, you can setup shared keys to automate it with no passwords. Much better then ssh.
You can use it to do complete backups or take snapshots. It's very scriptable and is only realy limited by your imagination.
For some examples:
http://aplawrence.com/Basics/rsync.html
http://www.mikerubel.org/computers/rsync_snapshots/
There is a interesting article about rdiff-backup, something that is designed to make backups easier but works in a similar fasion to rsync.
http://arstechnica.com/articles/columns/linux/linux-20060202.ars
On the 2nd page.