I just mad that pencil lead case marker and it is like the best thing ever.. dead ass, not sure how many pages back it was and im too lazy to find the post but here it is:
get one of those wide things that the pencil lead comes in for the mechanical pencils, the wide one not the diamond shaped one, duct tape the bottom if there is holes and remove the lead. drop some ink in there and fold a small peice of cloth so it fits in the top only problem is u gotta refill a lot