A simple little check-in to make sure a *-nix computer has all your basic needs.

doctor.awk

{ sum += $4 }
END { mb = sum / 1024
gb = mb / 1024
printf \"%.0f MB (%.2fGB) of available disk space\n\", mb, gb
}
EOF

doctor.sh

df -k / | awk -f doctor.awk

echo "You are: $(whoami)"
echo "Right now it's: $(date)"
echo
if [ ruby ]
  then
    echo "Ruby is installed"
  else
    echo "Ruby is not installed"
fi
if [ python ]
  then
    echo "Python is installed"
  else
    echo "Python is not installed"
fi
if [ perl ]
  then
    echo "Perl is installed"
  else
    echo "Perl is not installed"
fi