PowerDevil is an utility for KDE4 for laptop power management.
Version: 1.4.2PowerDevil is an utility for KDE4 for laptop power management. It consists of a Daemon (a KDED module), a KCModule to configure it, and will feature a Plasmoid soon.
Operating System: Linux
With PowerDevil you can set up preferences for lid Closing, Brightness, CPU scaling, Idle time, both when connected to AC and when on Battery. It is built upon Solid, and it's very lightweight and won't overkill your system resources. If you missed KLaptop or KPowersave, this might be the tool you were looking for.
There are no releases yet, since it is still in Playground, though it is already quite stable and feature full.