It can monitor the utilization of resources with the leds of the keyboard
BS Editor: Keyboard Led Monitor is a free software which can monitor the utilization of resources with the leds of the keyboard (num Lock, caps lock, scroll lock). The monitoring looks like the Battery Status bar of a mobile phone. Monitoring of CPU level, network traffic, memory and Swap usage, and battery level are supported. The software can be used with game modes also, like the program bl.

Battery monitoring is only activated if the AC adapter is plugged out, another monitor (or game mode) can be used when the battery is not in use. There is a security option which turns off the computer if the battery level < 4 %. Be very careful with this option, it runs a /usr/sbin/halt so the computer will chut down with no saving of your works !! A last point, ACPI support by kernel is required for battery monitoring. you can free download Keyboard Led Monitor 1.1.1 now.