Nowadays, at the not helpful level, I use FG.
However, before that, my "binder" was a collection of web pages. Each adventure had up to 6 sections; Table of Contents; Map; Encounters (the actual room description, treasure, monster lists, etc); Combat Stats for the monsters. Frequently, there was a 5th section, Plot, if I had a time-based/event-based adventure. Once or twice, I used Sounds (links to various clips), but I found that to be more work than I was willing to put in. And of course, all the sections linked to each other.
The world/campaign stuff was usually sloughed off to a public website/wiki. That was generally divided into 3 sections - House Rules (subdivided as appropriate), Setting (Countries, Geography, etc), and Campaign (Table Rules, Adventure Logs, etc.).