Here’s a file backup script I installed for a client. The original outline came from a post on the ubuntu forums (I forget where exactly), but it’s simple enough. It creates an archive in /tmp, zips it up, emails it then deletes the archive. If your target is a linux computer then it makes more sense to gzip it by adding a “z” to the tar options (i.e. tar -czf) and removing the zip line.

#!/bin/bash
#
# Simple file backup script, creates archive in /tmp and emails it.
#
# Software required:
#  zip
#  tar
#  mutt

# Variables
[email protected]
SOURCE="/home/user1 /home/user2"
SERVERNAME=server.example.com
MAIL=`which mutt`
ZIP=`which zip`
DATE=`date +%Y_%m_%d`
FILE=myfiles-$DATE.tar
DESTINATION=/tmp/$FILE
ZIPFILE=$DESTINATION.zip

# Actions
tar -cf $DESTINATION $SOURCE 2> /dev/null
$ZIP $ZIPFILE $DESTINATION
$MAIL -a $ZIPFILE -s "Backup for $DATE" -s "$SERVERNAME backup $DATE" $MAILADDR < /dev/null
rm $ZIPFILE $DESTINATION

For mutt to work you need an MTA (mail transport agent) such as postfix. If it’s not installed and you don’t need it for anything else, configure it as a satellite system (the Ubuntu/Debian packages prompt you on install and satellite system is an option). This prevents spammers from using it as a relay, and ensures the mail goes to your real mail server.