This really impressed me: cutting power usage by over 75% for a full lighting/video rig on tour:
The full system (including video) is exclusively LED and uses 140A 3phase (420A in total) when turned on fully. It's worth pointing out that LED lighting uses Red, Green and Blue LED's to make colours, with all 3 being on 100% to make white, therefore any colour effect only uses a percentage of the power. Traditional lighting uses a subtractive colour creation, with filters placed in front of a white source to remove the unwanted colour - therefore, in the case of red for example, using 100% of the power for a third of the light output.
http://www.radiohead.com/themostgiganticflyingmouthforsometime/ViewEntry.html?EntryID=52