Another good example is Japanese cling wrap, which is just so much better than everything I've seen in western supermarkets.

One of the things many fountain pen users complain about with Pilot is that their converters don't work like other fountain pens. But in each case there are specific design choices that shine. Their cartridges have wider openings than standard ink cartridges. In part this makes their cartridges and converters proprietary, but the wider mouth and the hinged lid on the cartridges makes for better ink flow.

The CON-40, often criticized for low ink capacity, fits their smaller pens, and has small agitators in the converter, allowing every last drop to get to the feed, and making cleaning easier. The CON-70, generally liked for its capacity, also has a unique feature of a metal tube that runs the length of the converter. This tube, which could have simply been a rod to hold the rubber stopper that enables pump filling, is a tube so that you can actually hold a blunt syringe to the tube mouth and squirt water straight to the back of the converter allowing you to clean it out properly.

I love using well-designed products, and their writing instruments are among my favorites.