After setting up a laptop with Ubuntu, one of the things that I typically like to do is add a the CPU Frequency Scaling Monitor applet (cpufreq-applet) to my main Gnome panel.

I typically work running large web applications (Grails…) that typically use a lot of CPU power when running tests, launching the apps or refactorings within an IDE.  I like the ability to quickly adjust the CPU ‘govenor’ which governs how the CPU is utilized from a power/performance perspective (see CPU Frequency Scaling in Linux for more).

Ubuntu 9.10 (Karmic Koala) uses Gnome 2.28.1 which requires authorization to change the CPU Frequency (which makes sense).  Earlier versions did not require this authorization since it is new in Gnome 2.28.

With policykit-1 (also new in Ubuntu 9.10) you can grant yourself authorization for the cpufreq-applet based on a user or group by creating a policy file (at /var/lib/polkit-1/localauthority/50-local.d/org.gnome.cpufreqselector.pkla for example) that looks something like this:
[org.gnome.cpufreqselector]
Identity=unix-user:YourUser
Action=org.gnome.cpufreqselector
ResultAny=no
ResultInactive=no
ResultActive=yes

Thanks to this post/discussion for pointing this out   be sure you change YourUser to your username or group that you wish to have authorized.

I don’t know of a policy GUI that works with policykit-1 yet, so let me know if you find something.

I also replaced the icons in the /usr/share/pixmaps/cpufreq-applet/ with something I found on  gnome-look.org