Cribbed right off the download page:
BattCursor shows the remaining battery charge in percent directly under the mouse cursor, and offers many other battery-saving features, including dim down the display brightness when inactive, automatically disable the Windows Sidebar, Aero Glass and much more.
And the best part: It costs nothing, worth seeing
BattCursor (no relation to the Caped Crusader) gives you a free method of managing your laptop’s battery usage that is so much better than the built-in “management” tools in Windows, you’ll wonder why Microsoft didn’t
steal it think of it themselves.
The author’s native language is apparently German, but the translation is perfectly understandable in the application itself, and only mildly odd on the Web site.