@yawaramin, I’m very fond of the documentation style one sees for Ruby and Python.
Examples: the Ruby string module documentation and the Python time module documentation.
The formatting in both of those is very clean and easy to read. The typesetting shows indicates very naturally to the reader what is important and what isn’t, where you should start and end reading any given topic, etc. I realize many people don’t recognize the importance of good typography in making it easier to read documentation, but it has major effects on usability.
Similarly, Paul Steckler and others are working on a conversion of the Coq documentation to Sphinx (which is the system used for Python’s documentation). Here is what it looked like before, which I find rather unreadable. Here’s what it looks like converted, which I think is vastly nicer.