Jupiter is a power management utility avaialble on SourceForge.net with a GUI for many advanced power features in Linux

Simple, easy to use hardware and power management applet for all i386 and x86_64 Linux laptops, and netbooks. A key component of the Aurora Linux distribution, also compatible with Fedora 12/13. Not supported on other distributions.

This saves you the trouble of managing power manually with sched_mc_power_savings, hdparm, laptop_mode and powertop.