I'm interested in how people use their binders for uses other than as a planner. Do you use a binder to learn a new subject? Do you have a binder for a specific project? :)
Since I split my A5 in to 'large' and 'small' (ring size) I use the large ring size one for all my reference information, contacts, stored notes, maps etc. And the small ring one for planning, with my two diary inserts and a few notes pages in between. Plus any pages I need to carry on a trip or for an event away from home. This keeps the planning one light in weight and not a burden to carry.
I am quite interested in answers to this question, too. Maybe it would be a good discussion point for FFAF?