Many Android devices don't indicate battery level in a way that easily represents the amount remaining.
Awesome Battery Indicator draws a unintrusive green bar across the top of your screen representing battery level in a way that does not require Root privileges.
Best part? It's free!
The size of the indicator corresponds to the battery percentage remaining, in relation to your screen width.
This is by far one of the best solutions for displaying your battery usage on your Android device. Much less intrusive, and easier to view and access than Widgets or notifications.
Future updates will include:
-Color customization *Done in 2.0!*
-Ability to draw the battery percentage value after the bar * Done in 2.1!*
-Color changing depending on battery level
-Hiding the color bar when certain apps are opened (Example: Hide when certain games are being played)
-Sizing *Done in 2.0!*
2/10/2013 (3.1): Fixed bug where it would always start on boot, even if you chose not to :). Sorry!
2/8/2013: Fixed auto start on boot for 4.0+ devices.