I used to use whatever was at hand for tokens. Coins. Bottle caps. Chips. Sometimes we'd eat the stuff we killed.

But my favorite was one time I grabbed a small piggy bank and described it was the big demon thing that had emerged from the back of the truck. Players were fighting it, and after a particularly nasty hit I said like "Your rifle shot punctures its grisly belly, and you see...". I picked up the piggy bank and pulled out the stopper. Coins spilled out onto the table.

"...countless smaller demons bursting out of the wounds, screaming and skittering at you."

Players lost their minds. A+ would traumatize players again.