You can download an example applet i'm doing for checking acpi throttling states in new centrino and speedsteps processors. The 0.1 release is almost done like the steps shown in this article. 0.2 release has a better project structure and some improvements at the presentation and code. 0.3 release manage how to update the image icons that mantains the info from filesystem. Future releases will improve the presentation and will take some other factors into account, as it is totally alpha software now.