The dollar had rallied a record 12 weeks in a row into October, and hedge funds and other large speculators continue to place bets on the dollar against other major currencies, according to a recent report from the Commodity Futures Trading Commission.
The dollar bandwagon makes sense: The Fed has ended quantitative easing and is expected to raise interest rates next year, taking away two headwinds for a stronger dollar. The dollar chart also tends to move inversely with oil prices, and the precipitous crash in oil prices also points to a stronger dollar. Meanwhile, the U.S. economy remains among the strongest in the world, while Europe and Japan continue to muddle along.
The greenback will stay strong for the next few years, said John Kicklighter, chief strategist at DailyFX.com. One reason is that the dollar is still a safe-haven currency, especially if the stock market melts down. Also, other major economies, like Japan and the euro zone, have been troubled. "That gives the dollar another advantage," he said.
Read MoreUnique ETFs to spice up your portfolio
The largest ETF that taps into a surging dollar is PowerShares DB US Dollar Index Bullish Fund (UUP), which is up 8 percent this year through Nov. 14. It tracks the dollar's performance against six other currencies: the euro, Japanese yen, British pound, Canadian dollar, Swedish krona and Swiss franc. The ETF is euro-heavy, composing 57.6 percent of fund allocation compared to just 13.6 percent for the yen, though it's still diversified among more than one currency.
The smaller, WisdomTree Bloomberg U.S. Dollar Bullish Fund (USDU), up near-6 percent through Nov. 14, pegs the dollar against 10 other developed and emerging market currencies, such as the Mexican peso and the Brazilian real. However, the euro has the top allocation spot at 31.36 percent, followed by the yen at 19.23 percent.
Read MoreInvestors look to ETFs as fund managers disappoint
Shorting the euro has been the hands-down winner so far. The largest ETF in the currency niche is ProShares UltraShort Euro (EUO), which is up a hefty 18.5 percent through Nov. 14 and uses leverage to double-down on a falling euro: It books profits when the euro falls. Kicklighter thinks that the dollar will be strong against the euro for at least another year. It will also be exceptionally volatile. "There's a good probability that the euro zone will suffer another recession before the euro stabilizes," he said.
The tiny ProShares Short Euro (EUFX), up 9.6 percent through Nov. 14 uses less leverage than the "Ultrashort" version, so upward ticks and dips are less magnified.