If you have ever faced a challenge to create a page containing a complex layout with lots of elements. Say, a complex form.
Then you know how difficult it can be to get is pixel perfect.
My method is adding a div with a grid image in it. (a 10 x 10 pixels image with a point on one corner.)
here is the code needed…
(for moz/firefox, with ie hacks added.)
background: url(opmaak/afb/grid.gif) 0 0;