GKfreq

gkfreq is a plugin for gkrellm2 which displays the current CPU speed using the "dynamic" cpufrequency scheme.
Requires kernel support for speedstep-centrino:

CONFIG_X86_SPEEDSTEP_CENTRINO=m
CONFIG_X86_SPEEDSTEP_CENTRINO_TABLE=y
CONFIG_X86_SPEEDSTEP_CENTRINO_ACPI=y

Download gkrellm-gkfreq 1.0

bbfreq displays CPU speed as a dockable application for blackbox/fluxbox or as a standalone application for other windowmanagers.