Simple Linux backup

I have found article about Mirdir on LWN. Mirdir provides a quick and easy way to make an ad hoc backup of important data. With it you can copy a file or directories to your keydisk, or save redundant copies of data you can't afford to lose. It tries to do only one thing, and do it well: mirror a directory. When searching more I found that there are few other tools available to do this job: rsnapshot based on rsync