Dramatically increase battery life on a Macbook Pro with 2 GPUs

There are numerous ways to increase battery life on laptops, but I'll talk for one specific issue on Macbook Pros that has a profound impact on battery life.

Some of the Macbook Pros have 2 graphics cards. Mine has one from Ati and one from Intel. The second is a slower one that should be used only when serious graphics power is not required. Unfortunately this mechanism is not that well thought up. It turns out that any application using a specific graphics library (forgot which one) triggers a switch to the more power-hungry GPU. Simple applications like Skype, Flash... are such, even though they would work fine with the Intel card. This shortens battery time.

Fortunately there's this guy Cody Krieger that made an application (<----- link) that can make this switch manual:

Do you see the applications that the switch depends on? Skype and Twitter!

It even can see whether the laptop is no battery power and take further action:

Perfect. Time on battery power increased with a couple of hours (from 3-4 to 5-6):

I'm pretty sure I can increase it further.