How to Fill a Piston Fountain Pen with Ink
For piston-fillers, you don't need a converter or cartridges (as the pen has the "converter" built right into the pen barrel") so all you need is a bottle of ink.
Kaweco Sport Eyedropper Conversion - A How-To
One of the best features of the Kaweco Sport is that you can easily and quickly turn it into an eyedropper - enabling you to hold a ton of ink, and if you're using the clear demonstrator, have a moving air bubble in a tube of ink to keep you entertained during long meetings.
Bottled Ink or Cartridges?
When I received my first fountain pen, it came with a single cartridge, and gift giver (Jon) included two extra cartridges.
Why Fountain Pens?
In other parts of the world today, including Europe and Asia, and before my generation in North America, fountain pens were widely available in a much lower price range for both school-aged learning and everyday use.