Hey,
moved out of my parent's house a good while ago and the electricity bill came in two years later for the previous year.
The electricity provider paid back 1000€ for the new and lowered power consumption of the last year. The current running gag is "kick your kids out, get a grand back!"
Overclocked fx-8350 room heater and another PC running 24/7 made quite a difference.
Out of curiosity: How is everyone's electricity bills? Have you made any hardware changes or other changes in general to specifically lower power consumption?