I've had this phone for over a month, and I am ashamed I didn't figure this out until now. As you all know, the short battery life is mainly due to the huge Captivate screen. I found out that there is another brightness setting for the stock browser. This setting is independent from the phone brightness setting. Along with using a black wallpaper, keeping the phone brightness and browser brightness all the way down, I found the battery is lasting noticeably longer.