the Esee RC-5 has one built into the micarta,
multi functional is ok but at the detrement of your knife handle??
if your in a position where your making a bow drill , then obviously there is some wood somewhere around to burn,...
so why not use some for this,..
i,m all for working knifes and have only 4 or 5 showy knifes but i cant see the point.
i will be making some fancy pants handle for my RC5 methinks