WIR Bank
The WIR Bank, formerly the Swiss Economic Circle (German: "Wirtschaftsring-Genossenschaft"), or WIR, is an independent complementary currency system in Switzerland that serves businesses in hospitality, construction, manufacturing, retail and professional services. WIR issues and manages a private currency, called the WIR Franc, which is used in combination with the Swiss Franc to generate dual-currency transactions.
Microstates and the European Union
Andorra, Monaco, San Marino, and the Vatican City use the euro through monetary agreements with the EU, and have been granted the right to issue a limited number of euro coins. They were allowed to do so as they had used or been tied to the old eurozone currencies. Liechtenstein, on the other hand, uses the Swiss franc.