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It is possible to greatly extend the usage time of a laptop or netbook running on battery by disabling various services and installing various packages.
What tricks or tips do people have for getting an extra hour or two out of their batteries?
Use powertop to see which programs are doing unneeded background processing such as beagle/tracker, weather notifications, gnome-do, and (if you don't need the internet) network-manager, mail-notifications.
sudo powertop --auto-tuneto set all tunable options to their GOOD settings.