There will be soon a efficient, very efficient PC from LENOVO which name is ThinkCentre M58p Eco Ultra Small . Apparently the PC was tested and mesured consumption was only about 35 watts while idle, and 58 watts of power at peak usage. It has a power supply that is 85% efficient when converting AC to DC power (15% escapes as heat).
The PC will be packaged in materials that are both 100% recycled and 100% recyclable. Also, the first ThinkCentre will be using post-consumer recycled plastics in its construction.
The new ThinkVantage Power Manager enables you to save energy and lower electricity costs across your business. System administrators can monitor and remotely control the amount of electricity used by all desktops in a PC fleet. Program your ThinkCentre desktops to shut down on evenings or weekends, and realize new efficiencies through Power Manager.