CPUClock is a simple app that allows you to monitor the fast and slow CPU speed settings and to change these settings. It also gives a readout of the 'current' CPU speed (updated every second) as the OS switches between 'Fast' and 'Slow', depending on the processor loading.
CPUClock has been tested successfully on the BeagleBoard (ARMv7/Cortex-A8/OMAP3 port) and the PandaBoard ES.
Note that CPUClock is only of use on the BeagleBoard, PandaBoard and similar modern hardware. It will not run on older hardware.
There is also an alternative implementation of CPUClock. This version is a configure tool and will appear in the configure tool window when $.!Boot is double clicked. It will allow the 'Fast' (and 'Slow' if you are so inclined) speed to be set, and the setting will be retained over a reboot/reset/power cycle. This version does not show the 'instantaneous' cpu speed as it switches between fast and slow, as does the full app.