My first PhD advisor was German, and he introduced me to LAMY pens. Everyone in our lab was given a hardcover notebook and a LAMY pen, and there were plenty of ink cartridges that we could use. I don’t use fountain pens these days, preferring pencil instead, but I remember how nice those pens were.

While I’m on the topic of German stationery, I regularly use my Staedtler eraser and pencil sharpener.