€ and $ coin design

The US Mint (nope, not the candy people... the people who make coins) is experimenting with coin designs.

I wonder what would happen if all these people would find out about Euroland? Where all the coins have the same design on one side, but the other side is different across countries. And they already got something like 10 designs (pardon me for not remembering how many Euro-countries there are) and as the 10 new EU members join it across the coming years, it will only be more fun with the designs. And both the Euro coins and the State Quarter Program coins are in active circulation.