I use indexes as I prepare various notebooks for later use. Having the list of pages and their titles as a permenant entry doesn't leave flexability to relocate sections. Could do a draft page first then make a permenant index page.
Having a great interest in Flight Simulators, the double columns provide clarity to the many categories of flying....instruments, technique, aircraft types, etc. It makes the search for information easy, thanks to the indexing system. The color coding is an added bonus.
For lawyers preparing for trial - binders that easily display the location of the various motions sections needed for trial (i.e. Pre-Trial Motions) then getting to the section without having to go through all the sections is great.
I tend to be disorganized with my paperwork. I don't file important papers in a timely manner. The Ready Index would be helping to contain these papers until I have the time to file them away.