Using black wallpaper and turning the screen brightness all the way down, has increased my battery life tremendously. I tried looking for a black wallpaper app, and found one, but it doesn't work on the Epic. So I used my camera, with the flash turned off, and my finger over the lens, to get a black photo. This along extended battery life, but with the black back ground, the widgets now pop, because of the contrast, so I was able to turn brightness all the way down. Between implementing these two things, I was able to go 18 hrs. and still have 40% battery life left. Plus I think the black wallpaper looks really good. Its a win win situation.