Shorting the US$

Added: PowerShares DB US Dollar Index Bearish (UDN)

The investment seeks to track the price and yield performance, before fees and expenses, of the Deutsche Bank Short US Dollar Futures index. The index is comprised solely of short futures contracts. The futures contract is designed to replicate the performance of being short the US Dollar against the Euro, Japanese Yen, British Pound, Canadian Dollar, Swedish Krona and Swiss Franc.
http://finance.yahoo.com/q?s=UDN

Curious to see how this ETF does over time. How will US$ do against a selection of other currencies? Does this pay off if there is inflation in the US? However, most of these other countries aren't that much better off, so relatively it may not amount to much.
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