Getting rid of the penny isn't a new thing; it has been done in Both Canada and Australia with no negative effects.
Currently the Penny costs more than its value to make and the U.S. still makes about 8-12 billion new cents each year. The cost of Copper and Zinc are only rising.
The point of currency is to encourage trade and purchases, and the Penny no longer does this. The power of the Penny is now lower than the half cent was when it was discontinued.
Think of how many pennies you use. Do you carry them with you or are they a result of paying for goods? Usually it is the later. A simple rounding rule, used in Canada and Australia, removes added change
We the Undersigned therefore petition that the US government halt the minting of Pennies, and gradually remove them from circulation