MaBaSoft (www.mabasoft.net) has revved Currency Assistant, a Mac OS X tool that lets you convert between 174 world currencies (all major circulating
currencies plus the 18 Eurozone legacy currencies), to version 3.2. It's ready for the upcoming OS X Yosemite.

Currency Assistant automatically updates exchange rates over the Internet using the rates published by the European Central Bank, the Bank of Canada, the International Monetary Fund, and the Bank of Italy. With the software, you can create multiple converters and manage currencies, import and convert series of amounts, calculate and convert the result of expressions, and log, save, export, and print your conversions.

Currency Assistant requires Mac OS X 10.6 or higher. It's currently being offered for US$8.95 for a single-user license. That's 50% off the usual price.