Right so im back from my course and I must say it was very worth while. One of the things that really perked my interest was DPS (Distributed Power Service). Which basically means that once you have Distributed Resource Scheduing configured correctly you can enable DPS and it will VMotion machines around based on load and put un-needed hosts into standby.

They Showed us this video to demonstrate it and its fantastic. Not only can you save all those pennies turning off all your old tin when you virtualize the OS but you can also save mony during non peak load times too.