I will look into the cpumem applet, however it seems the indicator from that applet would not ALWAYS be visible when using the N900 (like if the camera is on, or watching a full screen video, or when the N900 is in standby mode with the screen off).

Do you think that single LED really uses that much power, enough to impact battery life?

mmmmmmmmmmmm, no

'no' meaning the LED should not impact battery life too much in your opinion?

the battery has 1.320mAh and a normal rgb-led needs 20mA per color. so i guess it would be recognizeable but of course not compareable to cpu or display consumption.
(but i'm one of these people who fight for every single mA because i don't want to reload my phone every single night ^^)

You bring up very good points, I think though that power consumption would not be drastically impacted.

We should try this project out! Does anyone know how to compile a standard linux program for the N900?

The thread "System Busy Indicator (LED?)" with seven posts has been merged into this thread.

Can anyone think of a way to flash or turn on the LED using the command line on the N900?

Yes, it's possible to activate the LED from the command line.

Thanks, the problem is the instructions all seem to discuss devices prior to the N900. Based on the links in this thread I cannot figure out how to manually have the LED on the front of the device light up.

Does anyone have any thoughts?