The article A Dao of Web Design is a bit old now, but it’s well worth another look. I had a client today looking for pixel-perfect placement across multiple browsers & screen resolutions. That’s not what the web is about. Hours can be wasted getting line endings to be in exactly the right spot – and then on someone else’s computer it will probably be different anyway!
Embrace the control that the web puts in the hand of the user & you’ll sleep much better at night!