At Christmas, a friend with ME was talking about how much she struggles to write these days. A couple of weeks ago I bought her a fountain pen as a birthday gift, and she called this morning to say she was really surprised by how much easier it is to use. You don't have to grip a fountain pen nearly so hard as a ballpoint, so it doesn't tire your muscles out so quickly. I have dyspraxia, and have had to use them since I was at school – I can barely manage a sentence with any other kind of pen. Obviously it won't work for everyone, but I thought I'd pass it on in case it's useful. I use the Lamy plastic ones, which are cheap but still write smoothly. Ink cartridges are expensive, but you can re-use the same one dozens of times over by washing it out and using a syringe and a blunt needle to refill it!