Reuters reports that Google will be making a power consumption chart available as a part of a smart-metering campaign in the US. You then check your iGoogle page (you do have an iGoogle page, right?) to see when you consume how much power.
The solution seems quite simple and cheap. Similar pilot projects have already been conducted in Germany, with consumption charts shown elsewhere on the Web. And of course, Italy has had blanket smart metering for years, so we are all dragging our feet on this crucial future issue.