Yeah but I think the OP is about fragments (after the coconut's been cracked to get to the meat) That limits uses a bit. I wonder if there's any nutritional value to be gained from the shells? Tea? Ground into something else?
You can use c. shell in your brass shell cleaning machine.
Pieces have a limited use. Tengu, next time try not to break the shell. You can extract the meat by cutting a triangular hole between the eyes.