Dammit you guys, I'm getting stylus envy from reading this thread.
Just dug out the fountain pen my dad brought back from China a few years ago, and put in a fresh cartridge.
I also found a nice looking Scheaffer fountain pen, which Eleanor recognised as hers. Apparently I've been hiding it from her for quite a few years. She thought she had lost it. Don't think I'm getting that one back.
Update: the Chinese pen actually seems to write very nicely, after flushing out the nib with water to get things moving. I suspect the "Iridium tip - Germany" stamp may not be authentic, but oh well.