The US minted a half-penny from 1793 to 1857 when they stopped making them as their purchase power was so little it was felt they were no longer needed. That 1/2 cent is equal to the purchasing power of about 10 cents today. Essentially in 1858 the lowest value coin would be a 20 cent coin today. Excellent arguments can be made for eliminating both the penny and the nickel. With inflation, a penny is worth about 20% of what it was worth in 1974 and only 10% of what is was worth in 1950. In other words those in favor of saving the penny need to be willing to say that we should have had a 1/10 cent piece in 1950, only a 1000 to the dollar. Fun calculator available at
CPI Inflation Calculator