A few years back, I was in a book store and saw a step-by-step how to make a monkey's fist knot, so I memorised it (didn't really want to buy a whole book), went home and before long, the house was full of monkey's fists, ranging from small marble-sized knots to a big one with a golf ball inside.
In my video you'll see a range of rope flails at the end, with cores of steel, glass, wood and the big one with the golf ball. My favourite is the black leather one with a rip-cord handle and hardwood core.
This video isn't so much a tutorial as it is a time-lapse demonstration. Hope you likey!
*update - thanks for Feature and all the great comments! Good to know some people are finding this an inspiration or a refresher :)