"Lamy" Fountain Pens are simply the best pens to write with. I first started writing with fountain pens when I was 7, at my German-Brazilian school. Note that in Germany, it's the thing to do: all students write with "Fueller" or "Fuellfederhalter" (fountain pens). Smoothness, classic yet modern design and quality makes these pens my favorite.
TWSBI Eco My best clear pen to date. Write BUTTER smooth. Holds a lot of ink, too.