The Definitive "save my battery" Guide.
1. When I first got the Atrix, before turning it on, I charged it for 4 hours. After turning it on, I let it run until it died, then re-charged for 8 hours. I did that for a full week. They say that this isn't needed with the new-fangled batteries, but I have always done this, and have always gotten great results.
2. Live wallpapers are not your friend, especially in two circumstances: 1. you use your phone a lot, and 2. you use the stock unlock screen where everytime the phone wakes the live wallpaper is playing. Granted, they don't eat up much battery, but if you're looking to get every ounce/percentage out of your phone, it's a luxury you can leave at home.
3. Did you install a new launcher? If so, did you clear out BLUR? I had my BLUR interface up and running with widgets and shortcuts, etc, etc. When I switched to ADW I noticed an increase in battery drain. I re-loaded BLUR and deleted all apps, widgets, etc so BLUR is blank. I now have great battery life with ADW running.
4. Widgets - ugh. They're pretty, they're big, they're animated, and they eat battery like bees eat pollen. Be mindful of them, and be willing to accept the consequences of the "cool factor".
5. Screen timeout. Yes, it's annoying to unlock your phone every 5 minutes, but you do save battery life with a 1-minute or less timeout option set.
6. Close your apps! Many apps, games especially, are fantastic at running in the background on Android, but they're sucking battery. They all restore to your previous position quite well, so if you're done for a few hours, exit it instead of just going back to your launcher screen.
7. "back" vs. "home" - the back button (the reverse arrow) does a much better job of closing down programs than the home button which just brings up your home screen, leaving whatever you were doing to hungrily consume battery like zombies on a corpse.
8. "manage apps" is your friend - go to your app tray, hit the menu button, and select "manage apps" - you can see all the running apps and kill them selectively. Some, like Facebook, Skype, and others, will stay there as long as the phone is on once you use it, unless you kill it. Be forwarned though, you'll stop getting notifications if you do this - another informed tradeoff. I do this once every few days, or if the Atrix seems sluggish.
9. Screen brightness - the "auto" setting doesn't work all that well, but I highly recommend leaving it there, and/or using a screen brightness toggle widget on your home screen to manage this carefully. Screen brightness on maximum will yield the best viewing experience but it does drain battery the fastest of all.
10. Choose your BLUR accounts wisely - like widgets, if you have LinkedIn and Facebook connected through BLUR, it will run ALL THE TIME. Using the native apps from the market will definitely decrease your overall drain and give you better control over when and how your battery is consumed by those services.
11. Auto-kill or be killed - A good rule of thumb for me is to only auto-end a task if you know exactly what it is, and it didn't come with the phone. Chances are if you don't recognize it, even if it looks like something you don't need running, leave it be. If it's something you installed from the Market, and you want it to auto-end, have a field day. If you put something on the auto-end list that the Atrix needs, it will just keep re-starting it. This draws processor time and battery and isn't worth it.
12. (credit: Itsallgood) Check your profile - "settings -> battery" and look at the bottom half of the screen. The Atrix supports multiple battery saving profiles that allows you to control "night time" and whether to actively sync data all the time, never, or only during certain hours. Push mail and active data sync consumes battery at a steady pace. In addition, 3rd party apps (like Settings Profiles) can be downloaded to further tweak and customize everything from vibrate mode, screen, data sync, and more. The more customized your experience to fit your needs only when you need specific services, the better your battery life will be.