Backing up debian

[Joel Hammer]

I am finally making my cheapo lindows box into a honest machine by
installing a backup program. I just mount a drive on another computer,
run find -newer somedate and tar them and zip them.  Works OK. I fine
tune what files to tar with sed /file/d.

Now, my question is, on a debian machine, since I would be restoring from
CD for the operating system and I will download almost all my software
from the warehouse, what do I really need to backup? I have to get my
boot directory and /usr/local and /root and /home, but anything else?

Thanks,

Joel