I went to the gravel pit, where they crush rocks into gravel, and got, what they call a "worn out" conveyor belt.  I got about 100' for free.  I have runners along all of my pathways in the shop.  I also keep all of the large cardboard boxes, like washers, dryers, refers, etc. come in.  I flatten them out over the remaining floor.  It is amazing what a couple of layers of cardboard will do.  I used to worry about them catching fire but if a piece of hot metal jumps out of the tongs I just reach over and pick it up and have a small scorched area.  Never have seen any flame.  Then, too, if I spill oil on the cardboard while changing the oil on the truck the cardboard, not the concrete, catches it.  This area is not in the immediate area of the anvil.