There are numerous options available for enterprise PC Power Management. The latest is Utopia Power Manager - Enterprise Power Management:

Utopia Power Manager is a complete solution which supports saving open documents and Wake On LAN.

This product has been build over the last three years and is very comprehensive.
We would recommend the free trial to see how it compares to the other products.
ROI within 3-6 months.

More information/trial info is available from: