Most investors have a portfolio strategy that mirrors the movement of the major U.S. stock indexes. They achieve this through a combination of individual stocks and ETFs, and thus creating a diversity that brings the performance of the portfolio back to the mean and in line with the big name stocks.
Over the last few years, a number of ETF providers have launched investment vehicles that offer exposure to niche sectors of the market. The ETFs track everything from single commodity futures to small frontier markets in Southeast Asia. Risk-tolerant investors will want to note these excelling ETFs.

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Under-followed ETFs
Teucrium Corn Fund
(NYSE: CORN) trades like an ETF on the NYSE and is composed of three corn futures contracts. The fund began trading in early June and since that time, the price of corn has skyrocketed and CORN has gone along for the ride. Even with an expense ratio of 1%, the fund is a better option for most investors versus opening a futures trading account. Corn is not the only agricultural commodity doing well. Months of inclement weather around the globe, combined with increasing demand from emerging markets, have the sector on the rise. A recent USDA report regarding corn is what sent the fund higher in early October and has CORN futures looking bright.

One of the most hated sectors is the airline stocks. Unless, of course, you invested in the Guggenheim Airline ETF (NYSE:FAA) this year. The ETF is up 35% and trading at its best level ever. Recent earnings reports from the sector have shown increased earnings as well as higher ticket prices - a win-win for the sector. The ETF is heavily concentrated, with the top three stocks making up 50% of the allocation. They include the three big-name U.S. airlines: United Continental Holdings (NYSE:UAL), Delta Air Line (NYSE:DAL), and Southwest Airlines (NYSE:LUV). If you want exposure to the sector, FAA is hands-down a better choice than picking just one airline stock.

Developing Nations
Eastern Europe is a small region that is often overlooked by investors, especially Poland. The iShares MSCI Poland Investable ETF (NYSE:EPOL) began trading in late May and now investors have access to the country via a basket of stocks. The ETF trades with a low P/E ratio of 15.97 and pays a 1.3% dividend. Nearly half of the stocks in the ETF are financials, which is the norm for many developing nations. EPOL is aggressive, but with 37 stocks in the portfolio, the risk is mitigated.

The infrastructure build out in the emerging markets has been a hot topic for years, but until the recession ended, the related stocks did not rally. The PowerShares Emerging Markets Infrastructure ETF (NYSE:PXR), which began trading in late 2008, recently hit a new historic high on the back of the emerging market strength and the money flowing into infrastructure projects. This is one niche sector that has the ability to continue higher in the face of a slowing U.S. economy. (For more, see Re-evaluating Emerging Markets.)

Bottom Line
All four of these niche ETFs could find a home in investor's portfolios, but it comes down to each person's goals and risk tolerance. As always, please do your own due diligence before investing your money. (For related reading, check out 5 Ways To Find A Winning ETF.)

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