Charge

Charge is a little app that shows your notebook battery level as an adjustable floating icon. It's useful, because it shows important information in an obvious but unobtrusive way. Just leave the icon somewhere on your screen and it will continually show your battery status, from full to flat and charging back up again. Charge will show a notification when your battery is fully charged and when you are running low on power. You can double-click on the floating icon at any time to show a notification with more details.