I hate it when some article I’m reading fills the whole screen. It’s just too hard on my eyes to read a huge web page that uses my entire 1024 pixel wide screen.
So I wrote a bookmarklet for doing this:
Just drag the ColumnWidth bookmarket to your links toolbar. Click on it when you’re reading something big. Works best with clean, mostly textual pages. No guarantees. Only tested on Firefox: may or may not work on other browsers.
It just adds a 225px right & left margin to the page. Works for me, others could customize it for their taste.