The first and last, I can lay no claim to, they were entirely prompted by my child, but in the aftermath of them I realized what an excellent fine motor activity took place.
Writing your own music
Basically get a piece of manuscript paper and the child writes their own music. You can either print a piece up online or buy a pad of it at the music shop. If you wish you can introduce the child to the concepts of whole notes, single, quavers or minims, but again not really necessary. We simply figured out what the notes were after he'd filled up the page. Then we tried to pick it out on the piano with difficulty until we received assistance from a more musical friend and voila! What a pretty piece of music it turned out to be.
Sort of like the concept of instant messaging. Instead of having a conversation take a notebook (this also works very well with the NEO keyboard) write a comment down about anything (could be something happening in the room, outside the window, or a bunch of compliments like "I think you're great" which will usually elict a smile) and hand it to the child to write a response. If the child resists writing then scribe for them or reply to what they verbalise. Eventually they tend to become curious and grab the pen. It helps to keep it humorous. If the child is more visual depict a cartoon instead. Draw a picture and pass the book over and let them draw the next one.
Take an atlas and photocopy several pages of various maps which depict oceans in between the continents. Give the child a pencil, coloured pencils or pens and encourage them to create shipping routes between the countries or simply doodle on the photocopied map. Maps are fascinating and it's a engaging activity where the fine motor activity is incidental to something that's more interesting going on.