For those looking for better battery life, I've been using Lumos for a long time and love it. It helps battery life by adjusting the screen intensity based on the light meter reading. You can set the polling time, but I find it saves me battery. It also saves my eyes when I look at the clock in the middle of the night because it will set the screen brightness to minimum in the dark!
thread:
http://forum.xda-developers.com/showthread.php?t=450318
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