Is the way that the scroll bar disappears when it's not needed. Which means that when you view a page with more content than the previous one (or even worse; when the page you are viewing dynamically increases in length) it basically makes the page sort of 'jolt' to the side. It looks horrible! And when I first noticed it a long time ago, I thought it was that my pages were laid out differently when they weren't.

This problem doesnt appear to be in IE6, although it does in IE7! I know it's a long shot but I don't suppose there is anyway of counteracting it? Maybe with CSS or JavaScript?

Make the height/width of the body/largest div be 100%?

Sure there's a way of counteracting it - make sure your widest element is at least 22px LESS than the max page width - that's about the width of the scrollbar.

Oh, and I might also mention that most users pay very little attention to something like this

With IE7 the width is 24px atleast... I was making a page earlier that had width issues at 1000px on a 1024 resolution.