Many years ago I got hold of the first version of Windows NT (Version 3.1 for some strange, marketing related, reason). This was the beginning of "proper" 32 bit operating systems underneath Windows, a trend which has continued all the way to Windows XP and finally Vista.
However, as it was based on an Intel 486 chip with only 64 MBytes of memory the operating system used to struggle a bit. We used to have a game called "mouse waggling", where you would fire up the performance counter and see how much CPU load you could create just by moving the mouse pointer around the screen. Sad but fun (particularly on somebody else's computer). A good player could get up to 50 or 60%.
I tried the game today on Vista (it has some really nice performance displays in the sidebar). Except this time I was dragging a window, complete with contents, over a large and complex desktop. The needle does move, but nothing like as far as it used to. I guess this is down to the use of the graphics hardware to underpin the display system, either way it is impressive.