Show a growl notification every minute if battery is below threshold

battery_low.sh

#!/bin/bash
#
# Show a growl notification every minute if battery is below threshold.
# 
# Setup:
# 1. Install growlnotify
# 2. Adjust threshold in line 20 (here 656mAh)
# 3. Create line in crontab like this:
# * * * * * /path/to/script/battery_low.sh

charger=`/usr/sbin/system_profiler SPPowerDataType | grep "Connected:"`

if [[ "$charger" == *Yes* ]]
then
  exit
fi

rem=`/usr/sbin/system_profiler SPPowerDataType | grep -i "Charge remaining" | sed 's/[^0-9]//g'`

if [ "$rem" -lt "656" ]
then
  /usr/local/bin/growlnotify -n batteryAlert -p High -m "Battery getting low... ($rem mAh)"
fi