Okay, so you're on a 1600x900 screen. Or maybe 1200x900, if 4:3 laptops are still around, but horizontal space doesn't seem to be a problem for either of us.
Vertically, that's not all that much more than the 1920x1080 screens I regularly use, and I've not made any special effort to optimize vertical space on my setup.
My current screen has vertical space allocated like so:
46px: Firefox window border and tabs (a bit extra wasted space because I'm not in a maximized window, but rather a 960-wide half-screen window)
38px: Main address bar + search bar
25px: bookmarks bar
913px: Page content
18px: horizontal scrollbar and bottom window border
40px: Windows taskbar
Adjusting to a 900px screen height, that alone would give 733px for page content, or about 81%. This is a worst-case for my setup - simply maximizing the window would cause the horizontal scrollbar to disappear and the top window border to shrink, saving 17px and 16px, respectively. At this point, you should be up to 766px out of 900px, or 85%.
The next easy step is disabling the bookmarks bar, for 25px, and setting the Windows taskbar to auto-hide, saving 40px. That would give you 831px of page content, or 92%, which beats at least my installation of Chrome. That's pretty good, but I can do better:
100% of your screen is now devoted to page content. All bars and menus are automatically hidden.