There is no need for duplicated notes in this use case. Simply have one notebook & use tags "A to B" and "B to A". Tag each note appropriately. Tag the "take along either way" note with both tags. Then just search on the tag you're interested in at the time. Also, having duplicated notes increases your chances for error. If you have the "take along when switching" note duplicated & you realize you need to add something to it, you need to do it to both notes. By having only one note, you only need to make the change once. Using one notebook doesn't allow different sharing though. I often collect a lot of information that I collect in a "work notebook". Some of these notes however I want to share with colleagues. If I could put the same note in two different notebooks (like Springpad allows) then I could make edit's to the note in my "work notebook" and the changes reflected in the notebook that I'm sharing with others. If I only put the notebook in one area or the other, it slows down the workflow having to switch between notebooks and having similar notes, tagged appropriately spread across different notebooks.