This weekend, I ran by the bank to cash in several jars of change I had accumulated. I think it was five to ten pounds worth. All in all, it wound up being $40 in coins, roughly half in dimes, and the rest split between nickels and pennies. Most of the volume by far, however, was pennies. (I hoard quarters because I need them to do laundry.)
This got me to thinking, I can't even remember the last time I used a penny for any purpose other than making exact change just so I didn't get more pennies. You can't use them in any vending machine. I can't imagine anyone using them to pay for anything even as trivial as a Coke from a 7-11. So what's the point of keeping them in circulation?