Answer:
What has three ways out and just one way in?
Used left or right, I get to travel over cobblestone or gravel. Used up, I vie for sweet success, used down, I cause men great duress.
I saw a strange creature. Long, hard, and straight, thrusting into a round, dark opening. Preparing to discharge its load of lives. Puffing and squealing noises accompanied it, then a final screech as it slowed and stopped.
There are millions of me. I am very small but when moving fast I am deadly.
Two in a whole and four in a pair. And six in a trio you see. And eight's a quartet but what you must get. Is the name that fits just one of me?
hey are producers of pies and burgers and are great for tipping.