
I believe that Apple, Sun and a number of other desktop machine
manufacturers have agreed with the government to incorporate
power-saving techniques;  this is also something that governments in
other countries are likely to require in the future, so expect to see
it.  This may include the ability for the system to fully power down
the monitor, via a controllable power outlet, and power it back on
automatically.  (Is this a "sell" on screen saver software companies?)

Goals for "idle" power consumption have been set at something like 30
watts for the system, not including the monitor (? don't quote me on
this).

Note that in many businesses, the savings will be substantial,
especially if you factor in reduced load on air conditioning systems.
Sun did a study that indicated that simply powering off monitors for
the night would save the company (Sun itself) on the order of $1M per
year.  Putting other (and automatic) power-saving features in would
probably have greater than double that value.

Given that we are seeing more and more reason to leave our work and
home computers on (getting faxes, automatically getting email, ...),
building power consumption control into all machines has a potential to
cut ~2% off the national power consumption, based on data I heard.