Fountain pens for note-taking

Speed, instant starts, and lines fine enough for margins.

Note-taking is the highest-cadence writing there is: cap off, seven words, cap on, forty times an hour. Retractable and slip-cap designs earn their keep here, and fine, slightly dry setups keep marginalia legible at small sizes.

If your notes live on copy paper, this is the use-case where Japanese extra-fine and fine nibs go from specialist to obvious.