gkrellm-est is a GKrellM plugin that displays the current frequency of the processor, and allows the user to change it by clicking the label, either with left button (to increase it) or with the right one (to decrease it). It only works on NetBSD and with EST (Enhanced Speedstep Technology) processors, such as the Centrino. A driver for this was introduced in NetBSD-current on April, 30th, 2004.