Double your phone's standby battery life by making sure that Wi-Fi and other energy vampires are active only when you need them. Stick with the "balanced" profile for a modest improvement, or upgrade (for $4.99) to a version that sets rules for specific apps, day versus night usage, and more.
https://market.android.com/details?id=com.latedroid.juicedefender&hl=en
WIRED Tells you how much juice you're saving. Activity log shows which processes it's killing.
TIRED Halted connections can mean delayed notifications. Glitchy interface occasionally renders buttons inaccessible.