At 4:00am most of the Linux (and UNIX for that matter) machines start executing a bunch of scripts that clean up temporary files, update file databases, and all sorts of other maintainence work. For those, who know, I am talking about cron daemon. Obviously, such a heap of activity increases the power consumption of each individual computer and thus can be monitored by the electricity authority. And probably it is. The useful thing here is that this monitoring can be used for estimating the number of Linux/UNIX machines in the geographical area, such as a region, city, or, even, a country.
defenetly a nice idea. The only problem might be (and obviosly is) that such organizations as electrycity authority do not care much about the number of Linux/Unix users in the city/country.
But the fact mentioned by you can be used for those who want to track the number and have access to the electricity authority data :)
[1] Well, theoretically speaking, Electricity Authority of Cyprus is a government body, which means that it exists on the money of the taxpayers. Therefor, taxpayers can request certain information to be made public. That, in turn, may include power consumption numbers by hour (unless this is confidential for national security reasons). Having this information available, anyone can setup the estimation graph. :)
hm… havn’t thought of it like this. it makes thinks easier, but still – it is a theory until one will try it :)