These are far more satisfying than dot matrix or laser printers. I used to draw stage lighting plots with them in college in the mid-80's. So much fun to watch them work.
I worked in a construction company where we drawed blueprints in AutoCAD for these pen plotters. It was very soothing to see them work, but we had this pervert engineer who would caress the long brush's hairs under them and whisper sexy things. Unfortunately, that is irremediably linked in my mind to pen plotters.