At last count, you could invest in 15 different currencies through 24 unique ETFs. The yen and the euro have more than their fair share of possibilities on investments like the Euro Currency Trust (FXE), the Ultra Euro ProShares (ULE) and the UltraShort Euro ProShares (EUO).
Yet in the first 5 months of the year, the 5 currency ETFs with the highest returns seem to share several things in common. First, each represents a country that boasts higher interest rates than the yen or the U.S. dollar.
Full Story: http://www.etfexpert.com/etf_expert/2009/06/etf-expert-5-months-5-currency-etfs-double-digit-percentage-gains.html