This is an edited version of a post that originally appeared on a blog called The Michigan Telephone Blog, which was written by a friend before he decided to stop blogging. It is reposted with his permission. Comments dated before the year 2013 were originally posted to his blog.
I have not tried or tested this, but just wanted to point it out as it might prove useful to some readers. I still prefer MondoRescue for a full system backup, but I can see how this might also come in handy in certain situations:
How to do Painless MySQL Server Backups with AutoMySQLBackup (Linux.com)