for sites about software, i think that the text needs to be your focus.
but a huge wall of non-formatted text is jarring. you need a visual rhythm at moves your eyes from element to element.

* disregarding the site menus and sidebars *

underscore's docs:
- http://underscorejs.org
even though the method name, description, and example are all the same font size, the subtle padding adds to the readability. same same way the border beside the example separates itself from the rest while keeping a united block.
- http://underscorejs.org/#filter
their annotated source is pretty cool too:
- http://underscorejs.org/docs/underscore.html

i also like a well laid out github wiki:
- https://github.com/mbostock/d3/wiki/Selections

and as i said on irc, magnum-ci's docs:
- https://magnum-ci.com/docs/api