Just got a fantastic 20" widescreen lcd and its fantastic set the res of it to its native of 1680x1050. Desktop and games look awesome. However I noticed since I did this web pages seem to always have large empty spaces on the left and right hand sides..they dont seem to be optimised for widescreen? Is there an addon or plugin in Firefox that makes it all widescreen and fill the entire screen rather than just the middle?
Depends on the site really. You could override the page's CSS. Fact is though that lots of sites aren't designed for widescreen. You have say a centred container div with a width of ~700px. Really can't think of a way to do it even with CSS since different pages use different layouts. Even something where the width is 100% it still might look odd with the inline elements flowing on that far.