Software to monitor computer power usage

[PaulStat]

I stumbled across the thread that showed peoples graphs from using the intelligent power monitor things from British gas.

My question is, is there any nice free software out there that does the same thing but monitors power usage for the computer? Something like motherboard monitor does but more geared towards the power usage of hours, days, weeks etc.

 

[semi-pro waster]

I can't imagine it would be very accurate at all, you'd need some sort of hardware monitor and then just pro-rata the costs/usage from that I would suspect.

//edit and sorry, no I don't know of anything that does it in software.