I'm currently running 10.04 on a Clevo W760CU laptop. This computer has a "power save" button that slows down the fan and presumably clocks something down (I don't know what, the manual doesn't say). My laptop does not have a light to indicate whether this feature is in use (the issue is dealt with using software on Windows).

The function fully works, but sometimes I forget if it is enabled or not. How can I find out if it is? I want to write a little indicator, but I don't know how to check or where to look if power save is enabled.