Have you ever experienced a full disk on a server or a desktop? Not fun. This script would normally be run as a cron job and would notify you by email if any drive's free disk space has passed below a certain threshold. The code could be better; I wrote this one a long time ago when I was a bit of a n00b and I was in a rush as well. I might make take a look at it again and see if I can make some improvements.
Low Disk Space Warning Script