That's an interesting point. Here in Ontario we have smart electrical meters so that the hydro company can charge you different rates depending on the time of day; running the A/C during work hours is more expensive than running it at night, and so on. It would be interesting if household devices were aware of these cost-of-power schedules so that you could put laundry in a dryer and set it to "dry in the 12 hours, whenever electricity is cheapest".
Running the washing machine at night when it's cheapest may not be desired, rather running it when no one is home and it's off peak. Turning on alarms, switching off lights, dropping temperature automatically. Allowing individuals in the household to have their own work patterns and temperature presets etc.
The key point is that it has to be effortless. No complex interfaces or setup. Plug, play, forget. And only in the next 12-24 months do enough technologies hit critical mass to make it economically feasible.