That's a great description of the billing "system", Doug! I can see how it puts a strong incentive to maintain low usage over time, though the bumps are quite dramatic there!

With billing like that, replacing your energy hog computer would seem a no-brainer --> or at least disconnecting the power from it for much of the time. 18 hours a day seems an unlikely "necessity".

I practically "live" on the internet here, but my main computer (big notebook) is rarely on for 18 hours a day.

Our 24/7 server is on all of the time though. I'm in the process of replacing that 25W power hog with a new (hopefully) ~18W 20W power hog: a Jetway mini-ITX board with a single-core Atom N455 CPU. Hey, the new board even handles 1080p video playback under Linux!

Cheers