Okay, I have the same problem myself and, to be honest, I haven't implemented a solution yet. Just done research. But I'll share my findings.

http://del.icio.us/tphyahoo/backup

My current opinion (to summarize what you get from my bookmarks): if you're okay spending a little money for a commercial service, and want user friendly, windows oriented (tho probably works for nix too): carbonite. Pretty cheap, lotsa buzz, looks pretty good.

http://www.carbonite.com/

If you want a DIY solution,

http://backuppc.sourceforge.net/info.html

good thread on this at

http://www.aaronsw.com/weblog/lazybackup