Updated with new settings design, also added Network settings and 'Show Desktop' feature - shows your wallpaper/live-wallpaper in full screen.
Note: This doesn't open, it is a Widget not an app. Add on homescreen with Menu -> Add -> Widgets -> Battery Widget or Apps -> Widgets -> Battery Widget
Description Permissions Usage by @BruceProgrammer (thx):For quick access to the controls for turning Wi-Fi on and off, this application requires device permissions to view Wi-Fi state, change Wi-Fi state, and "prevent device from sleeping". This application does not, however, do anything to prevent the device from sleeping.
In order to display whether the GPS receiver is on or off, for display purposes only, this application requires the additional device permission to access "fine (GPS) location". This application, however, does not actually ever access device location information.
Open Source at http://code.google.com/p/batterywidget/