The Microsoft Windows XP pagefile is used in addition to any existing physical ram, and windows uses it in a very similar way. It is needed because applications and services cannot function properly when limited to the amount you have installed, so Microsoft developed the Pagefile as a way of covering itself from falling over. So it makes sense that anything that can be done to optimise the Pagefile will greatly benefit your system.

There is a definate current need to assess our energy use, from EU initiatives and global warming, right down to the pennies (pounds more like) spent on the electric bill. You may think that this is a small matter, but I have personally implemented energy saving tactics into large and small sized businesses and seen a massive effect.