I compiled this module which sets the brightness of a led according to the load average in the past 1 minute.

Compiled module here: http://my.arava.co.il/~matan/770/n900/ledtrig-dim.ko

To actually use this you need fixed leds driver and somehow prevent mce from constantly touching the led. See this thread for details: http://talk.maemo.org/showthread.php?t=44267


See here for module source:
http://www.mail-archive.com/linux-em.../msg02597.html